display(1)


SYNOPSIS

   gm animate [ options ... ] file [ [ options ... ] file ... ]

   gm batch [ options ... ] [ script ]

   gm benchmark [ options ... ] subcommand

   gm compare [ options ... ] reference-image [  options  ...  ]  compare-
   image [ options ... ]

   gm  composite  [  options  ... ] change-image base-image [ mask-image ]
   output-image

   gm conjure [ options ] script.msl [ [ options ] script.msl ]

   gm convert [ [ options ... ] [ input-file ...  ]  [  options  ...  ]  ]
   output-file

   gm display [ options ... ] file ...  [ [options ... ]file ... ]

   gm identify file [ file ... ]

   gm import [ options ... ] file

   gm mogrify [ options ... ] file ...

   gm  montage  [  options ... ] file [ [ options ... ] file ... ] output-
   file

   gm time subcommand

   gm version

DESCRIPTION

    GraphicsMagick's gm  provides  a  suite  of  utilities  for  creating,
   comparing,  converting,  editing,  and  displaying  images.  All of the
   utilities are provided as sub-commands of a single gm executable:

   animate displays an animation (e.g. a  GIF  file)  on  any  workstation
   display running an X server.

   batch  executes  an  arbitary  number  of  the  utility  commands (e.g.
   convert) in the form of a  simple  linear  batch  script  in  order  to
   improve  execution efficiency, and/or to allow use as a subordinate co-
   process under the control of an arbitrary script or program.

   benchmark executes one of the other utility commands (e.g. convert) for
   a  specified  number  of  iterations,  or  execution  time, and reports
   execution time and other profiling information such as CPU utilization.
   Benchmark  provides  various  operating  modes  including executing the
   command with a varying  number  of  threads,  and  alternate  reporting
   formats such as comma-separated value (CSV).

   compare compares two images and reports difference statistics according
   to  specified  metrics  and/or  outputs  an   image   with   a   visual
   representation  of  the  differences.   It  may also be used to test if
   images are similar within a  particular  range  and  specified  metric,
   returning a truth value to the executing environment.

   composite  composites  images  (blends  or  merges  images together) to
   create new images.

   conjure  interprets  and  executes  scripts  in  the  Magick  Scripting
   Language (MSL).

   convert converts an input file using one image format to an output file
   with the same or differing image format  while  applying  an  arbitrary
   number of image transformations.

   display  is  a  machine  architecture  independent image processing and
   display facility. It can display an image on  any  workstation  display
   running an X server.

   identify  describes the format and characteristics of one or more image
   files. It will also report if an image is incomplete or corrupt.

   import reads an image from any  visible  window  on  an  X  server  and
   outputs  it  as  an  image  file.  You can capture a single window, the
   entire screen, or any rectangular portion of the screen.

   mogrify transforms an image or a sequence of images.  These  transforms
   include image scaling, image rotation, color reduction, and others. The
   transmogrified image overwrites the original image.

   montage creates a composite by combining several separate  images.  The
   images  are  tiled  on  the  composite image with the name of the image
   optionally appearing just below the individual tile.

   time executes a subcommand and reports  the  user,  system,  and  total
   execution time consumed.

   version  reports  the  GraphicsMagick  release version, maximum sample-
   depth, copyright notice, supported features, and the options used while
   building the software.

   The GraphicsMagick utilities recognize the following image formats:

   Name  Mode Description
    o  3FR       r-- Hasselblad Photo RAW
    o  8BIM      rw- Photoshop resource format
    o  8BIMTEXT  rw- Photoshop resource text format
    o  8BIMWTEXT rw- Photoshop resource wide text format
    o  APP1      rw- Raw application information
    o  APP1JPEG  rw- Raw JPEG binary data
    o  ART       r-- PF1: 1st Publisher
    o  ARW       r-- Sony Alpha DSLR RAW
    o  AVS       rw+ AVS X image
    o  BIE       rw- Joint Bi-level Image experts Group
                     interchange format
    o  BMP       rw+ Microsoft Windows bitmap image
    o  BMP2      -w- Microsoft Windows bitmap image v2
    o  BMP3      -w- Microsoft Windows bitmap image v3
    o  CACHE     --- Magick Persistent Cache image format
    o  CALS      rw- Continuous Acquisition and Life-cycle
                     Support Type 1 image
    o  CAPTION   r-- Caption (requires separate size info)
    o  CIN       rw- Kodak Cineon Format
    o  CMYK      rw- Raw cyan, magenta, yellow, and black
                     samples (8 or 16 bits, depending on
                     the image depth)
    o  CMYKA     rw- Raw cyan, magenta, yellow, black, and
                     matte samples (8 or 16 bits, depending
                     on the image depth)
    o  CR2       r-- Canon Photo RAW
    o  CRW       r-- Canon Photo RAW
    o  CUR       r-- Microsoft Cursor Icon
    o  CUT       r-- DR Halo
    o  DCM       r-- Digital Imaging and Communications in
                     Medicine image
    o  DCR       r-- Kodak Photo RAW
    o  DCX       rw+ ZSoft IBM PC multi-page Paintbrush
    o  DNG       r-- Adobe Digital Negative
    o  DPS       r-- Display PostScript Interpreter
    o  DPX       rw- Digital Moving Picture Exchange
    o  EPDF      rw- Encapsulated Portable Document Format
    o  EPI       rw- Adobe Encapsulated PostScript
                     Interchange format
    o  EPS       rw- Adobe Encapsulated PostScript
    o  EPS2      -w- Adobe Level II Encapsulated PostScript
    o  EPS3      -w- Adobe Level III Encapsulated PostScript
    o  EPSF      rw- Adobe Encapsulated PostScript
    o  EPSI      rw- Adobe Encapsulated PostScript
                     Interchange format
    o  EPT       rw- Adobe Encapsulated PostScript with MS-DOS
                     TIFF preview
    o  EPT2      rw- Adobe Level II Encapsulated PostScript
                     with MS-DOS TIFF preview
    o  EPT3      rw- Adobe Level III Encapsulated PostScript
                     with MS-DOS TIFF preview
    o  EXIF      rw- Exif digital camera binary data
    o  FAX       rw+ Group 3 FAX (Not TIFF Group3 FAX!)
    o  FITS      rw- Flexible Image Transport System
    o  FRACTAL   r-- Plasma fractal image
    o  FPX       rw- FlashPix Format
    o  GIF       rw+ CompuServe graphics interchange format
    o  GIF87     rw- CompuServe graphics interchange format
                     (version 87a)
    o  GRADIENT  r-- Gradual passing from one shade to
                     another
    o  GRAY      rw+ Raw gray samples (8/16/32 bits,
                     depending on the image depth)
    o  HISTOGRAM -w- Histogram of the image
    o  HRZ       r-- HRZ: Slow scan TV
    o  HTML      -w- Hypertext Markup Language and a
                     client-side image map
    o  ICB       rw+ Truevision Targa image
    o  ICC       rw- ICC Color Profile
    o  ICM       rw- ICC Color Profile
    o  ICO       r-- Microsoft icon
    o  ICON      r-- Microsoft icon
    o  IDENTITY  r-- Hald CLUT identity image
    o  IMAGE     r-- GraphicsMagick Embedded Image
    o  INFO      -w+ Image descriptive information and
                      statistics
    o  IPTC      rw- IPTC Newsphoto
    o  IPTCTEXT  rw- IPTC Newsphoto text format
    o  IPTCWTEXT rw- IPTC Newsphoto wide text format
    o  JBG       rw+ Joint Bi-level Image experts Group
                     interchange format
    o  JBIG      rw+ Joint Bi-level Image experts Group
                     interchange format
    o  JNG       rw- JPEG Network Graphics
    o  JP2       rw- JPEG-2000 JP2 File Format Syntax
    o  JPC       rw- JPEG-2000 Code Stream Syntax
    o  JPEG      rw- Joint Photographic Experts Group
                     JFIF format
    o  JPG       rw- Joint Photographic Experts Group
                     JFIF format
    o  K25       r-- Kodak Photo RAW
    o  KDC       r-- Kodak Photo RAW
    o  LABEL     r-- Text image format
    o  M2V       rw+ MPEG-2 Video Stream
    o  MAP       rw- Colormap intensities and indices
    o  MAT       r-- MATLAB image format
    o  MATTE     -w+ MATTE format
    o  MIFF      rw+ Magick Image File Format
    o  MNG       rw+ Multiple-image Network Graphics
    o  MONO      rw- Bi-level bitmap in least-significant-
                     -byte-first order
    o  MPC       rw+ Magick Persistent Cache image format
    o  MPEG      rw+ MPEG-1 Video Stream
    o  MPG       rw+ MPEG-1 Video Stream
    o  MRW       r-- Minolta Photo Raw
    o  MSL       r-- Magick Scripting Language
    o  MTV       rw+ MTV Raytracing image format
    o  MVG       rw- Magick Vector Graphics
    o  NEF       r-- Nikon Electronic Format
    o  NULL      r-- Constant image of uniform color
    o  OTB       rw- On-the-air bitmap
    o  P7        rw+ Xv thumbnail format
    o  PAL       rw- 16bit/pixel interleaved YUV
    o  PALM      rw- Palm Pixmap
    o  PBM       rw+ Portable bitmap format (black and white)
    o  PCD       rw- Photo CD
    o  PCDS      rw- Photo CD
    o  PCL       -w- Page Control Language
    o  PCT       rw- Apple Macintosh QuickDraw/PICT
    o  PCX       rw- ZSoft IBM PC Paintbrush
    o  PDB       rw+ Palm Database ImageViewer Format
    o  PDF       rw+ Portable Document Format
    o  PEF       r-- Pentax Electronic File
    o  PFA       r-- TrueType font
    o  PFB       r-- TrueType font
    o  PGM       rw+ Portable graymap format (gray scale)
    o  PGX       r-- JPEG-2000 VM Format
    o  PICON     rw- Personal Icon
    o  PICT      rw- Apple Macintosh QuickDraw/PICT
    o  PIX       r-- Alias/Wavefront RLE image format
    o  PLASMA    r-- Plasma fractal image
    o  PNG       rw- Portable Network Graphics
    o  PNG24     rw- Portable Network Graphics, 24 bit RGB
                     opaque only
    o  PNG32     rw- Portable Network Graphics, 32 bit RGBA
                     semitransparency OK
    o  PNG8      rw- Portable Network Graphics, 8-bit
                     indexed, binary transparency only
    o  PNM       rw+ Portable anymap
    o  PPM       rw+ Portable pixmap format (color)
    o  PREVIEW   -w- Show a preview an image enhancement,
                     effect, or f/x
    o  PS        rw+ Adobe PostScript
    o  PS2       -w+ Adobe Level II PostScript
    o  PS3       -w+ Adobe Level III PostScript
    o  PSD       rw- Adobe Photoshop bitmap
    o  PTIF      rw- Pyramid encoded TIFF
    o  PWP       r-- Seattle Film Works
    o  RAF       r-- Fuji Photo RAW
    o  RAS       rw+ SUN Rasterfile
    o  RGB       rw+ Raw red, green, and blue samples
    o  RGBA      rw+ Raw red, green, blue, and matte samples
    o  RLA       r-- Alias/Wavefront image
    o  RLE       r-- Utah Run length encoded image
    o  SCT       r-- Scitex HandShake
    o  SFW       r-- Seattle Film Works
    o  SGI       rw+ Irix RGB image
    o  SHTML     -w- Hypertext Markup Language and a
                     client-side image map
    o  STEGANO   r-- Steganographic image
    o  SUN       rw+ SUN Rasterfile
    o  SVG       rw+ Scalable Vector Gaphics
    o  TEXT      rw+ Raw text
    o  TGA       rw+ Truevision Targa image
    o  TIFF      rw+ Tagged Image File Format
    o  TILE      r-- Tile image with a texture
    o  TIM       r-- PSX TIM
    o  TOPOL     r-- TOPOL X Image
    o  TTF       r-- TrueType font
    o  TXT       rw+ Raw text
    o  UIL       -w- X-Motif UIL table
    o  UYVY      rw- 16bit/pixel interleaved YUV
    o  VDA       rw+ Truevision Targa image
    o  VICAR     rw- VICAR rasterfile format
    o  VID       rw+ Visual Image Directory
    o  VIFF      rw+ Khoros Visualization image
    o  VST       rw+ Truevision Targa image
    o  WBMP      rw- Wireless Bitmap (level 0) image
    o  WMF       r-- Windows Metafile
    o  WPG       r-- Word Perfect Graphics
    o  X         rw- X Image
    o  X3F       r-- Foveon X3 (Sigma/Polaroid) RAW
    o  XBM       rw- X Windows system bitmap (black
                     and white)
    o  XC        r-- Constant image uniform color
    o  XCF       r-- GIMP image
    o  XMP       rw- Adobe XML metadata
    o  XPM       rw- X Windows system pixmap (color)
    o  XV        rw+ Khoros Visualization image
    o  XWD       rw- X Windows system window dump (color)
    o  YUV       rw- CCIR 601 4:1:1 or 4:2:2 (8-bit only)

       Modes:
                 r   Read
                 w   Write
                 +   Multi-image

   Support  for  some  of  these  formats  require  additional programs or
   libraries.  See README in the source package for where to find optional
   additional software.

   Note,  a  format delineated with + means that if more than one image is
   specified, frames are combined into  a  single  multi-image  file.  Use
   +adjoin if you want a single image produced for each frame.

   Your installation might not support all of the formats in the list.  To
   get an accurate listing of the formats  supported  by  your  particular
   configuration, run "gm convert -list format".

   Raw  images  are  expected  to  have  one  byte  per pixel unless gm is
   compiled in 16-bit quantum mode or in 32-bit quantum  mode.  Here,  the
   raw  data  is  expected  to  be  stored  two  or  four bytes per pixel,
   respectively, in most-significant-byte-first order.  For  example,  you
   can  tell  if  gm  was  compiled  in 16-bit mode by typing "gm version"
   without any options, and looking  for  "Q:16"  in  the  first  line  of
   output.

FILES AND FORMATS

   By  default,  the image format is determined by its magic number, i.e.,
   the first few bytes of the file. To specify a particular image  format,
   precede   the   filename   with  an  image  format  name  and  a  colon
   (i.e.ps:image) or  specify  the  image  type  as  the  filename  suffix
   (i.e.image.ps).   The  magic  number takes precedence over the filename
   suffix and the prefix takes precedence over the magic  number  and  the
   suffix in input files.  When a file is read, its magic number is stored
   in the "image->magick" string.   In  output  files,  the  prefix  takes
   precedence  over  the  filename  suffix,  and the filename suffix takes
   precedence over the "image->magick" string.

   To read the "built-in" formats (GRANITE, H, LOGO, NETSCAPE, PLASMA, and
   ROSE)  use a prefix (including the colon) without a filename or suffix.
   To read the XC format, follow the colon with a color specification.  To
   read  the CAPTION format, follow the colon with a text string or with a
   filename prefixed with the at symbol (@).

   When you specify X  as  your  image  type,  the  filename  has  special
   meaning.  It specifies an X window by id, name, or root. If no filename
   is specified, the window is selected  by  clicking  the  mouse  in  the
   desired window.

   Specify  input_file  as  -  for  standard  input,  output_file as - for
   standard output.  If input_file has the extension .Z or .gz,  the  file
   is uncompressed with uncompress or gunzip respectively.  If output_file
   has the extension .Z or .gz, the file is compressed using with compress
   or gzip respectively.

   Use  an optional index enclosed in brackets after an input file name to
   specify a desired subimage of  a  multi-resolution  image  format  like
   Photo  CD  (e.g.  "img0001.pcd[4]")  or  a  range for MPEG images (e.g.
   "video.mpg[50-75]"). A subimage specification  can  be  disjoint  (e.g.
   "image.tiff[2,7,4]").  For  raw  images,  specify  a  subimage  with  a
   geometry (e.g. -size 640x512 "image.rgb[320x256+50+50]").  Surround the
   image name with quotation marks to prevent your shell from interpreting
   the square brackets. Single images are written with  the  filename  you
   specify.  However,  multi-part  images  (e.g.,  a multi-page PostScript
   document with +adjoin specified) may be written with the  scene  number
   included  as part of the filename. In order to include the scene number
   in the filename, it is necessary to include a  printf-style  %d  format
   specification in the file name and use the +adjoin option. For example,

       image%02d.miff

   writes   files   image00.miff,   image01.miff,   etc.   Only  a  single
   specification is allowed within an output filename. If  more  than  one
   specification  is  present, it will be ignored. It is best to embed the
   scene number in the base part of the file name, not in  the  extension,
   because the extension will not be a recognizeable image type.

   When  running  a commandline utility, you can prepend an at sign @ to a
   filename to read a list of image filenames  from  that  file.  This  is
   convenient in the event you have too many image filenames to fit on the
   command line.

OPTIONS

   Options are processed in command line order. Any option you specify  on
   the  command line remains in effect for the set of images that follows,
   until the set is terminated by the appearance of any option  or  -noop.
   Some  options  only  affect  the decoding of images and others only the
   encoding.  The latter can appear after the final group of input images.

   This is a combined  list  of  the  command-line  options  used  by  the
   GraphicsMagick   utilities   (animate,   compare,  composite,  convert,
   display, identify, import, mogrify and montage).

   In this document, angle brackets ("<>")  enclose  variables  and  curly
   brackets  ("{}")  enclose  optional  parameters.  For  example,  "-fuzz
   <distance>{%}" means you can use the option "-fuzz 10" or "-fuzz 2%".

   -adjoin
          join images into a single multi-image file

          By default, all images of an image sequence are  stored  in  the
          same  file.  However,  some  formats  (e.g. JPEG) do not support
          storing more than one image per file and only the first frame in
          an  image  sequence  will be saved unless the result is saved to
          separate files. Use +adjoin to force saving multiple  frames  to
          multiple  numbered  files.  If  +adjoin is used, then the output
          filename must include a printf  style  formatting  specification
          for the numeric part of the filename.  For example,

              image%02d.miff

   -affine <matrix>
          drawing transform matrix

          This  option provides a transform matrix {sx,rx,ry,sy,tx,ty} for
          use by subsequent -draw or -transform options.

   -antialias
          remove pixel aliasing

          By default antialiasing algorithms are used when drawing objects
          (e.g.   lines)   or  rendering  vector  formats  (e.g.  WMF  and
          Postscript). Use  +antialias  to  disable  use  of  antialiasing
          algorithms.  Reasons  to  disable  antialiasing include avoiding
          increasing colors in the image, or improving rendering speed.

   -append
          append a set of images

          This option creates a single  image  where  the  images  in  the
          original  set are stacked top-to-bottom.  If they are not of the
          same width, any narrow images will be expanded to fit using  the
          background  color.   Use  +append to stack images left-to-right.
          The set of images is terminated by the appearance of any option.
          If the -append option appears after all of the input images, all
          images are appended.

    -asc-cdl <spec>
          apply ASC CDL color transform

          Applies ("bakes in") the ASC CDL, which  is  a  format  for  the
          exchange  of  basic  primary  color  grading information between
          equipment and software from different manufacturers. The  format
          defines  the  math for three functions: slope, offset and power.
          Each function uses a number for the red, green, and  blue  color
          channels  for  a total of nine numbers comprising a single color
          decision.  The  tenth  number  (optional)  is   for   chromiance
          (saturation) as specified by ASC CDL 1.2.

          The  argument  string is comma delimited and is in the following
          form (but without invervening spaces or line breaks)

            redslope,redoffset,redpower:
            greenslope,greenoffset,greenpower:
            blueslope,blueoffset,bluepower:
            saturation

          with   the    unity    (no    change)    specification    being:
          "1.0,0.0,1.0:1.0,0.0,1.0:1.0,0.0,1.0:1.0"

   -authenticate <string>
          decrypt image with this password

          Use  this option to supply a password for decrypting an image or
          an image sequence, if it is being read from a format such as PDF
          that  supports  encryption.   Encrypting images being written is
          not supported.

   -auto-orient
          orient (rotate) image so it is upright

          Adjusts the image orienation so that it is suitable for viewing.
          Uses  the  orientation  tag  obtained  from the image file or as
          supplied by the -orient option.

   -average
          average a set of images

          The set of images is terminated by the appearance of any option.
          If  the  -average  option appears after all of the input images,
          all images are averaged.

   -backdrop
          display the image centered on a backdrop.

          This backdrop covers the entire workstation screen and is useful
          for  hiding other X window activity while viewing the image. The
          color of the backdrop is specified as the foreground color  (X11
          default is black).  Refer to "X Resources", below, for details.

   -background <color>
          the background color

          The  color  is  specified  using  the format described under the
          -fill option.

   -black-threshold red[,green][,blue][,opacity]
          pixels below the threshold become black

          Use  -black-threshold  to  set  pixels  with  values  below  the
          specified  threshold to minimum value (black). If only one value
          is supplied, or the red, green, and blue values  are  identical,
          then  intensity  thresholding  is  used.  If the color threshold
          values are not  identical  then  channel-based  thresholding  is
          used,  and color distortion will occur. Specify a negative value
          (e.g. -1) if you want a channel to be ignored but you do want to
          threshold  a  channel later in the list. If a percent (%) symbol
          is appended, then the values are  treated  as  a  percentage  of
          maximum range.

   -blue-primary <x>,<y>
          blue chromaticity primary point

   -blur <radius>{x<sigma>}
          blur the image with a Gaussian operator

          Blur with the given radius and standard deviation (sigma).

   -border <width>x<height>
          surround the image with a border of color

          See -geometry for details about the geometry specification.

   -bordercolor <color>
          the border color

          The  color  is  specified  using  the format described under the
          -fill option.

   -borderwidth <geometry>
          the border width

   -box <color>
          set the color of the annotation bounding box

          The color is specified using  the  format  described  under  the
          -fill option.

          See -draw for further details.

   -channel <type>
          the type of channel

          Choose  from:  Red,  Green, Blue, Opacity, Matte, Cyan, Magenta,
          Yellow, Black, or Gray.

          Use this option to extract a particular channel from the  image.
          Opacity,  for  example,  is  useful  for  extracting the opacity
          values from an image.

   -charcoal <factor>
          simulate a charcoal drawing

   -chop <width>x<height>{+-}<x>{+-}<y>{%}
          remove pixels from the interior of an image

          Width and height give the number of columns and rows to  remove,
          and  x  and y are offsets that give the location of the leftmost
          column and topmost row to remove.

          The x offset normally specifies the leftmost column  to  remove.
          If  the  -gravity  option  is  present  with NorthEast, East, or
          SouthEast gravity, it gives the distance leftward from the right
          edge of the image to the rightmost column to remove.  Similarly,
          the y offset normally specifies the topmost row to  remove,  but
          if  the  -gravity  option  is  present with SouthWest, South, or
          SouthEast gravity, it specifies the  distance  upward  from  the
          bottom edge of the image to the bottom row to remove.

          The  -chop option removes entire rows and columns, and moves the
          remaining corner blocks leftward and upward to close the gaps.

   -clip  apply the clipping path, if one is present

          If a clipping path is present, it will be applied to  subsequent
          operations.

          For example, if you type the following command:

              gm convert -clip -negate cockatoo.tif negated.tif

          only the pixels within the clipping path are negated.

          The  -clip feature requires the XML library.  If the XML library
          is not present, the option is ignored.

   -coalesce
          merge a sequence of images

          Each image N in the sequence after Image 0 is replaced with  the
          image created by flattening images 0 through N.

          The set of images is terminated by the appearance of any option.
          If the -coalesce option appears after all of the  input  images,
          all images are coalesced.

   -colorize <value>
          colorize the image with the pen color

          Specify  the  amount  of  colorization  as a percentage. You can
          apply separate colorization values to the red, green,  and  blue
          channels  of  the image with a colorization value list delimited
          with slashes (e.g. 0/0/50).

          The -colorize option may be used in conjunction  with  -modulate
          to produce a nice sepia toned image like:

              gm convert input.ppm -modulate 115,0,100 \
                        -colorize 7,21,50 output.ppm.

   -colormap <type>
          define the colormap type

          Choose between shared or private.

          This  option  only  applies  when the default X server visual is
          PseudoColor or GRAYScale. Refer to -visual for more details.  By
          default, a shared colormap is allocated. The image shares colors
          with other X clients.  Some image colors could be  approximated,
          therefore  your  image  may  look  very different than intended.
          Choose Private and the image colors appear exactly as  they  are
          defined.  However,  other  clients  may  go technicolor when the
          image colormap is installed.

   -colors <value>
          preferred number of colors in the image

          The actual number of colors in the image may be less  than  your
          request, but never more. Note, this is a color reduction option.
          Images with less unique colors than specified with  this  option
          will  have  any duplicate or unused colors removed. The ordering
          of an existing color palette may be altered. When converting  an
          image  from  color  to  grayscale, convert the image to the gray
          colorspace before reducing the number of colors since  doing  so
          is most efficient. Refer to <a href="quantize.html">quantize for
          more details.

          Note, options -dither, -colorspace, and  -treedepth  affect  the
          color reduction algorithm.

   -colorspace <value>
          the type of colorspace

          Choices  are:  CineonLog,  CMYK,  GRAY,  HSL,  HWB,  OHTA,  RGB,
          Rec601Luma, Rec709Luma, Rec601YCbCr,  Rec709YCbCr,  Transparent,
          XYZ, YCbCr, YIQ, YPbPr, or YUV.

          Color reduction, by default, takes place in the RGB color space.
          Empirical evidence suggests that distances in color spaces  such
          as  YUV  or  YIQ correspond to perceptual color differences more
          closely than do distances in RGB space.  These color spaces  may
          give  better  results  when  color  reducing an image.  Refer to
          quantize for more details.  Two gray colorspaces are  supported.
          The  Rec601Luma space is based on the recommendations for legacy
          NTSC television (ITU-R BT.601-5).  The Rec709Luma space is based
          on  the  recommendations  for  HDTV (Rec. ITU-R BT.709-5) and is
          suitable for use with computer graphics,  and  for  contemporary
          CRT   displays.   The  GRAY  colorspace  currently  selects  the
          Rec601Luma  colorspace  by  default  for  backwards   compatibly
          reasons. This default may be re-considered in the future.

          Two  YCbCr  colorspaces  are supported. The Rec601YCbCr space is
          based on the recommendations for legacy NTSC  television  (ITU-R
          BT.601-5).  The Rec709CbCr space is based on the recommendations
          for HDTV (Rec.  ITU-R BT.709-5) and is suitable for suitable for
          use  with  computer graphics, and for contemporary CRT displays.
          The YCbCr colorspace specification is equivalent toRec601YCbCr.

          The  Transparent  color  space  behaves  uniquely  in  that   it
          preserves the matte channel of the image if it exists.

          The  -colors  or  -monochrome option, or saving to a file format
          which requires color reduction, is required for this  option  to
          take effect.

   -comment <string>
          annotate an image with a comment

          Use  this option to assign a specific comment to the image, when
          writing to an image  format  that  supports  comments.  You  can
          include  the image filename, type, width, height, or other image
          attribute by embedding special format  characters  listed  under
          the  -format option.  The comment is not drawn on the image, but
          is embedded in the image  datastream  via  a  "Comment"  tag  or
          similar mechanism.  If you want the comment to be visible on the
          image itself, use the -draw option.

          For example,

               -comment "%m:%f %wx%h"

          produces an image comment of MIFF:bird.miff 512x480 for an image
          titled bird.miff and whose width is 512 and height is 480.

          If the first character of string is @, the image comment is read
          from a file titled by the remaining characters in the string.

   -compose <operator>
          the type of image composition

          The description of  composition  uses  abstract  terminology  in
          order  to  allow  the  the  description  to be more clear, while
          avoiding constant values which  are  specific  to  a  particular
          build  configuration.  Each  image  pixel is represented by red,
          green, and blue levels (which  are  equal  for  a  gray  pixel).
          MaxRGB  is the maximum integral value which may be stored in the
          red, green, or blue channels of the image. Each image pixel  may
          also  optionally (if the image matte channel is enabled) have an
          associated  level   of   opacity   (ranging   from   opaque   to
          transparent),  which  may  be used to determine the influence of
          the pixel color when compositing the pixel  with  another  image
          pixel.  If  the image matte channel is disabled, then all pixels
          in the image are treated as opaque.   The  color  of  an  opaque
          pixel  is  fully  visible while the color of a transparent pixel
          color is entirely absent (pixel color is ignored).

          By definition, raster images have a rectangular shape. All image
          rows  are  of  equal length, and all image columns have the same
          number of rows. By treating the  opacity  channel  as  a  visual
          "mask"  the rectangular image may be given a "shape" by treating
          the opacity channel as a cookie-cutter  for  the  image.  Pixels
          within  the shape are opaque, while pixels outside the shape are
          transparent. Pixels on the boundary of the shape may be  between
          opaque   and   transparent  in  order  to  provide  antialiasing
          (visually smooth edges).  The  description  of  the  composition
          operators use this concept of image "shape" in order to make the
          description of the operators easier to understand. While  it  is
          convenient  to  describe the operators in terms of "shapes" they
          are by no means limited to mask-style operations since they  are
          based  on  continuous  floating-point  mathematics  rather  than
          simple boolean operations.

          By default, the Over composite operator is used.  The  following
          composite operators are available:

               Over
               In
               Out
               Atop
               Xor
               Plus
               Minus
               Add
               Subtract
               Difference
               Divide
               Multiply
               Bumpmap
               Copy
               CopyRed
               CopyGreen
               CopyBlue
               CopyOpacity
               CopyCyan
               CopyMagenta
               CopyYellow
               CopyBlack

          The behavior of each operator is described below.

           Over

                The result will be the union of the two image shapes, with
                opaque areas of change-image obscuring base-image  in  the
                region of overlap.

           In

                The  result  is  simply  change-image  cut by the shape of
                base-image. None of the image data of base-image  will  be
                in the result.

           Out

                The  resulting  image  is  change-image  with the shape of
                base-image cut out.

           Atop

                The result is the same shape as base-image,  with  change-
                image obscuring base-image where the image shapes overlap.
                Note this differs from over because the portion of change-
                image  outside  base-image's  shape does not appear in the
                result.

           Xor

                The result is the image data from  both  change-image  and
                base-image that is outside the overlap region. The overlap
                region will be blank.

           Plus

                The result is just the  sum  of  the  image  data.  Output
                values are cropped to MaxRGB (no overflow). This operation
                is independent of the matte channels.

           Minus

                The result of change-image -  base-image,  with  underflow
                cropped  to  zero.  The  matte  channel is ignored (set to
                opaque, full coverage).

           Add

                The result of change-image  +  base-image,  with  overflow
                wrapping around (mod MaxRGB+1).

           Subtract

                The  result  of  change-image - base-image, with underflow
                wrapping around  (mod  MaxRGB+1).  The  add  and  subtract
                operators    can    be    used   to   perform   reversible
                transformations.

           Difference

                The result of  abs(change-image  -  base-image).  This  is
                useful for comparing two very similar images.

           Divide

                The  result  of  change-image / base-image. This is useful
                for  improving  the  readability  of  text   on   unevenly
                illuminated  photos  (by  using a gaussian blurred copy of
                change-image as base-image).

           Multiply

                The result of change-image * base-image.  This  is  useful
                for the creation of drop-shadows.

           Bumpmap

                The result base-image shaded by change-image.

           Copy

                The  resulting  image  is base-image replaced with change-
                image. Here the matte information is ignored.

           CopyRed

                The resulting image  is  the  red  channel  in  base-image
                replaced  with  the red channel in change-image. The other
                channels are copied untouched.

           CopyGreen

                The resulting image is the  green  channel  in  base-image
                replaced with the green channel in change-image. The other
                channels are copied untouched.

           CopyBlue

                The resulting image is  the  blue  channel  in  base-image
                replaced  with the blue channel in change-image. The other
                channels are copied untouched.

           CopyOpacity

                The resulting image is the opacity channel  in  base-image
                replaced  with  the  opacity  channel in change-image. The
                other channels are copied untouched.

           CopyCyan

                The resulting image is  the  cyan  channel  in  base-image
                replaced  with the cyan channel in change-image. The other
                channels  are  copied  untouched.  Use  of  this  operator
                requires that base-image be in CMYK(A) colorspace.

           CopyMagenta

                The  resulting  image is the magenta channel in base-image
                replaced with the magenta  channel  in  change-image.  The
                other  channels are copied untouched. Use of this operator
                requires that base-image be in CMYK(A) colorspace.

           CopyYellow

                The resulting image is the yellow  channel  in  base-image
                replaced  with  the  yellow  channel  in change-image. The
                other channels are copied untouched. Use of this  operator
                requires that base-image be in CMYK(A) colorspace.

           CopyBlack

                The  resulting  image  is  the black channel in base-image
                replaced with the black channel in change-image. The other
                channels  are  copied  untouched.  Use  of  this  operator
                requires that base-image  be  in  CMYK(A)  colorspace.  If
                change-image  is  not in CMYK space, then the change-image
                pixel intensities are used.

   -compress <type>
          the type of image compression

          Choices are: None, BZip, Fax, Group4, JPEG, Lossless, LZW,  RLE,
          Zip, or LZMA.

          Specify  +compress  to store the binary image in an uncompressed
          format.  The default is the compression type  of  the  specified
          image file.

          "Lossless"  refers  to lossless JPEG, which is only available if
          the JPEG library has been patched to support it. Use of lossless
          JPEG is generally not recommended.

          Use  the -quality option to set the compression level to be used
          by JPEG, PNG, MIFF, and MPEG encoders. Use the  -sampling-factor
          option  to  set the sampling factor to be used by the DPX, JPEG,
          MPEG, and YUV encoders for downsampling the chroma channels.

   -contrast
          enhance or reduce the image contrast

          This option  enhances  the  intensity  differences  between  the
          lighter  and  darker  elements  of  the  image. Use -contrast to
          enhance the image or +contrast to reduce the image contrast.

          For a more pronounced effect you can repeat the option:

              gm convert rose: -contrast -contrast rose_c2.png

   -convolve <kernel>
          convolve image with the specified convolution kernel

          The kernel is specified as a comma-separated  list  of  floating
          point  values, ordered left-to right, starting with the top row.
          The order of the kernel is determined by the square root of  the
          number of entries.  Presently only square kernels are supported.

   -create-directories
          create output directory if required

          Use  this  option  with  -output-directory  if  the  input paths
          contain subdirectories and  it  is  desired  to  create  similar
          subdirectories  in  the  output directory.  Without this option,
          mogrify will fail if the  required  output  directory  does  not
          exist.

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

          See -geometry for details about the geometry specification.

          The  width  and  height  give the size of the image that remains
          after cropping, and x and y are offsets that give  the  location
          of  the top left corner of the cropped image with respect to the
          original image.  To specify the amount to be removed, use -shave
          instead.

          If the x and y offsets are present, a single image is generated,
          consisting of the pixels from the cropping region.  The  offsets
          specify  the  location  of the upper left corner of the cropping
          region measured downward and rightward with respect to the upper
          left  corner  of  the  image.  If the -gravity option is present
          with  NorthEast,  East,  or  SouthEast  gravity,  it  gives  the
          distance  leftward from the right edge of the image to the right
          edge of the cropping region.  Similarly, if the -gravity  option
          is  present  with  SouthWest,  South,  or SouthEast gravity, the
          distance is measured upward between the bottom edges.

          If the x and y offsets are  omitted,  a  set  of  tiles  of  the
          specified   geometry,   covering  the  entire  input  image,  is
          generated.  The rightmost tiles and the bottom tiles are smaller
          if  the  specified geometry extends beyond the dimensions of the
          input image.

   -cycle <amount>
          displace image colormap by amount

          Amount defines the  number  of  positions  each  colormap  entry
          isshifted.

   -debug <events>
          enable debug printout

          The  events  parameter  specifies which events are to be logged.
          It can be either None, All, or a comma-separated list consisting
          of  one or more of the following domains: Annotate, Blob, Cache,
          Coder,   Configure,   Deprecate,   Error,   Exception,   Locale,
          Render,Resource,  TemporaryFile,  Transform,  Warning,  X11,  or
          User.  For example, to log cache and blob events, use

              gm convert -debug "Cache,Blob" rose: rose.png

          The "User" domain is normally  empty,  but  developers  can  log
          "User" events in their private copy of GraphicsMagick.

          Use the -log option to specify the format for debugging output.

          Use +debug to turn off all logging.

          An  alternative  to  using  -debug  is  to  use the MAGICK_DEBUG
          environment variable. The allowed values  for  the  MAGICK_DEBUG
          environment variable are the same as for the -debug option.

   -deconstruct
          break down an image sequence into constituent parts

          This  option compares each image with the next in a sequence and
          returns the maximum bounding region of any pixel differences  it
          discovers.   This  method can undo a coalesced sequence returned
          by the -coalesce option, and is useful  for  removing  redundant
          information from a GIF or MNG animation.

          The  sequence  of  images is terminated by the appearance of any
          option.  If the -deconstruct option appears  after  all  of  the
          input images, all images are deconstructed.

   -define <key>{=<value>},...
          add  coder/decoder  specific  options This option creates one or
          more definitions for coders and decoders to  use  while  reading
          and  writing image data. Definitions may be passed to coders and
          decoders to control options that are specific to  certain  image
          formats.  If  value is missing for a definition, an empty-valued
          definition of a flag will be created with  that  name.  This  is
          used  to control on/off options. Use +define <key>,... to remove
          definitions previously created. Use +define "*"  to  remove  all
          existing definitions.

          The following definitions may be created:

           cineon:colorspace={rgb|cineonlog}

                Use  the  cineon:colorspace  option  when reading a Cineon
                file to specify the colorspace the Cineon file uses.  This
                overrides  the  colorspace  type implied by the DPX header
                (if any).

           dpx:bits-per-sample=<value>

                If the dpx:bits-per-sample key is defined,  GraphicsMagick
                will  write DPX images with the specified bits per sample,
                overriding any existing depth value. If this option is not
                specified,  then  the value is based on the existing image
                depth value from the original image file. The DPX standard
                supports  bits  per sample values of 1, 8, 10, 12, and 16.
                Many DPX readers demand a sample size of 10 bits with type
                A padding (see below).

           dpx:colorspace={rgb|cineonlog}

                Use  the  dpx:colorspace option when reading a DPX file to
                specify the colorspace the DPX file uses.  This  overrides
                the colorspace type implied by the DPX header (if any).

           dpx:packing-method={packed|a|b|lsbpad|msbpad}

                DPX  samples  are  output within 32-bit words. They may be
                tightly packed end-to-end  within  the  words  ("packed"),
                padded  with  null bits to the right of the sample ("a" or
                "lsbpad), or padded with null bits  to  the  left  of  the
                sample  ("b"  or "msbpad"). This option only has an effect
                for sample sizes of 10 or 12  bits.  If  samples  are  not
                packed,  the  DPX standard recommends type A padding. Many
                DPX readers demand a sample size of 10 bits  with  type  A
                padding.

           dpx:pixel-endian={lsb|msb}

                Allows  the user to specify the endian order of the pixels
                when reading or writing the DPX files. Sometimes  this  is
                useful  if the file is (or must be) written incorrectly so
                that  the  file  header  and  the  pixels  use   different
                endianness.

           dpx:swap-samples={true|false}

                GraphicsMagick  strives  to adhere to the DPX standard but
                certain aspects of the standard can be quite confusing. As
                a  result,  some  10-bit  DPX  files  have  Red  and  Blue
                interchanged,  or  Cb  and  Cr  interchanged  due  to   an
                different  interpretation  of the standard, or getting the
                wires crossed. The swap-samples  option  may  be  supplied
                when  reading  or  writing in order to read or write using
                the necessary sample order.

           jp2:rate=<value>

                Specify  the  compression  factor  to  use  while  writing
                JPEG-2000  files. The compression factor is the reciprocal
                of the compression ratio. The valid range is 0.0  to  1.0,
                with 1.0 indicating lossless compression. If defined, this
                value overrides the -quality setting. The default  quality
                setting of 75 results in a rate value of 0.06641.

           jpeg:block-smoothing={true|false}

                Enables  or  disables  block smoothing when reading a JPEG
                file (default enabled).

           jpeg:dct-method=<value>

                Selects the IJG JPEG library DCT  implementation  to  use.
                The  encoding  implementations  vary in speed and encoding
                error. The available choices for value are  islow,  ifast,
                float,  default  and  fastest. Note that fastest might not
                necessarily be fastest  on  your  CPU,  depending  on  the
                choices  made when the JPEG library was built and how your
                CPU behaves.

           jpeg:fancy-upsampling={true|false}

                Enables or disables fancy upsampling when reading  a  JPEG
                file (default enabled).

           jpeg:optimize-coding={true|false}

                Selects  if  huffman  encoding  should  be  used.  Huffman
                encoding is enabled by default, but may  be  disabled  for
                very  large  images  since  it  encoding requires that the
                entire image  be  buffered  in  memory.  Huffman  encoding
                produces  smaller  JPEG  files  at  the  expense  of added
                compression time and memory consumption.

           jpeg:preserve-settings

                If the jpeg:preserve-settings flag is  defined,  the  JPEG
                encoder  will use the same "quality" and "sampling-factor"
                settings that were found in the input file, if  the  input
                was  in  JPEG format. These settings are also preserved if
                the input is a JPEG file and the output is a JNG file.  If
                the colorspace of the output file differs from that of the
                input file, the  quality  setting  is  preserved  but  the
                sampling-factors are not.

           pcl:fit-to-page

                If  the  pcl:fit-to-page flag is defined, then the printer
                is requested to scale the  image  to  fit  the  page  size
                (width and/or height).
           pdf:use-cropbox={true|false}

                If   the   pdf:use-cropbox  flag  is  set  to  true,  then
                Ghostscript is requested to apply the PDF crop box.

           pdf:stop-on-error={true|false}

                If  the  pdf:stop-on-error  flag  is  set  to  true,  then
                Ghostscript  is  requested to stop processing the PDF when
                the first error is encountered.  Otherwise it will attempt
                to process all requested pages.

           ps:imagemask

                If  the  ps:imagemask  flag  is  defined, the PS3 and EPS3
                coders will create Postscript files  that  render  bilevel
                images  with  the Postscript imagemask operator instead of
                the image operator.

           tiff:alpha={unspecified|associated|unassociated}

                Specify the  TIFF  alpha  channel  type  when  reading  or
                writing  TIFF  files,  overriding  the  normal  value. The
                default alpha channel type for new  files  is  unspecified
                alpha.   Existing   alpha   settings  are  preserved  when
                converting from one TIFF file to another. When a TIFF file
                uses associated alpha, the image pixels are pre-multiplied
                (i.e.  altered)  with  the  alpha  channel.   Files   with
                "associated" alpha appear as if they were alpha composited
                on a black background when the matte channel is  disabled.
                If the unassociated alpha type is selected, then the alpha
                channel is saved without altering  the  pixels.  Photoshop
                recognizes  associated  alpha as transparency information,
                if the file is saved with unassociated  alpha,  the  alpha
                information  is  loaded  as  an independent channel.  Note
                that for many years, ImageMagick and GraphicsMagick marked
                TIFF  files  as  using  associated alpha, without properly
                pre-multiplying the pixels.

           tiff:fill-order={msb2lsb|lsb2msb}

                If the tiff:fill-order key is defined, GraphicsMagick will
                use  it to determine the bit fill order used while writing
                TIFF files. The normal default is "msb2lsb", which matches
                the  native  bit  order  of  all  modern  CPUs.  The  only
                exception to this is when Group3 or Group4 FAX compression
                is  requested since FAX machines send data in bit-reversed
                order and therefore  RFC  2301  recommends  using  reverse
                order.

           tiff:group-three-options=<value>

                If    the   tiff:group-three-options   key   is   defined,
                GraphicsMagick will use it to set the group3  options  tag
                when  writing group3-compressed TIFF.  Please see the TIFF
                specification for the usage  of  this  tag.   The  default
                value is 4.

           tiff:ignore-tags=<tags>

                If the tiff:ignore-tags key is defined, then it is used as
                a list of  comma-delimited  integer  TIFF  tag  values  to
                ignore  while  reading  the  TIFF file.  This is useful in
                order to be able to read files which which otherwise  fail
                to  read  due  to problems with TIFF tags.  Note that some
                TIFF tags are required in order to be  able  to  read  the
                image data at all.

           tiff:report-warnings={false|true}

                If  the  tiff:report-warnings  key  is  defined and set to
                true,  then  TIFF  warnings  are  reported  as  a  warning
                exception  rather  than  as  a  coder  log  message.  Such
                warnings are reported after the image  has  been  read  or
                written.  Most TIFF warnings are benign but sometimes they
                may help deduce problems  with  the  TIFF  file,  or  help
                detect  that  the TIFF file requires a special application
                to read successfully due to  the  use  of  proprietary  or
                specialized extensions.

           tiff:sample-format={unsigned|ieeefp}

                If  the  tiff:sample-format key is defined, GraphicsMagick
                will use it to determine  the  sample  format  used  while
                writing  TIFF  files.  The  default is "unsigned". Specify
                "ieeefp" in order to write floating-point TIFF files  with
                float   (32-bit)   or  double  (64-bit)  values.  Use  the
                tiff:bits-per-sample  define  to  determine  the  type  of
                floating-point value to use.

           tiff:max-sample-value=<value>

                If    the    tiff:max-sample-value    key    is   defined,
                GraphicsMagick will use the assigned value as the  maximum
                floating   point  value  while  reading  or  writing  IEEE
                floating point TIFFs. Otherwise the maximum value  is  1.0
                or  the value obtained from the file's SMaxSampleValue tag
                (if present). The floating point  data  is  currently  not
                scanned  in  advance  to  determine  a best maximum sample
                value so if the range is not 1.0, or  the  SMaxSampleValue
                tag is not present, it may be necessary to (intelligently)
                use this parameter to properly read a file.

           tiff:min-sample-value=<value>

                If   the    tiff:min-sample-value    key    is    defined,
                GraphicsMagick  will use the assigned value as the minimum
                floating  point  value  while  reading  or  writing   IEEE
                floating  point  TIFFs. Otherwise the minimum value is 0.0
                or the value obtained from the file's SMinSampleValue  tag
                (if present).

           tiff:bits-per-sample=<value>

                If the tiff:bits-per-sample key is defined, GraphicsMagick
                will write images with  the  specified  bits  per  sample,
                overriding  any  existing depth value. Value may be any in
                the range of 1 to 32, or 64 when  the  default  ´unsigned'
                format  is  written,  or  16/32/24/64  if IEEEFP format is
                written.   Please  note  that  the   baseline   TIFF   6.0
                specification  only  requires  readers  to  handle certain
                powers of two, and the values to be handled depend on  the
                nature  of  the  image  (e.g. colormapped, grayscale, RGB,
                CMYK).

           tiff:samples-per-pixel=<value>

                If the tiff:samples-per-pixel key is defined to  a  value,
                the  TIFF  coder  will  write TIFF images with the defined
                samples per pixel, overriding  any  value  stored  in  the
                image. This option should not normally be used.

           tiff:rows-per-strip=<value>

                Allows  the  user  to  specify the number of rows per TIFF
                strip.  Rounded up to a multiple of  16  when  using  JPEG
                compression. Ignored when using tiles.

           tiff:strip-per-page=true

                Requests that the image is written in a single TIFF strip.
                This  is  normally  the  default  when  group3  or  group4
                compression   is   requested   within  reasonable  limits.
                Requesting a single strip for large images may  result  in
                failure  due  to  resource  consumption  in  the writer or
                reader.

           tiff:tile

                Enable writing tiled TIFF (rather than stripped) using the
                default  tile  size.  Tiled TIFF organizes the image as an
                array of smaller images (tiles) in order to enable  random
                access.

           tiff:tile-geometry=<width>x<height>

                Specify  the  tile  size  to use while writing tiled TIFF.
                Width and height should be a multiple of 16. If the  value
                is  not  a  multiple  of 16, then it will be rounded down.
                Enables tiled TIFF if it has  not  already  been  enabled.
                GraphicsMagick  does  not  use tiled storage internally so
                tiles need  to  be  converted  back  and  forth  from  the
                internal   scanline-oriented   storage   to  tile-oriented
                storage. Testing with typical RGB images shows that useful
                square  tile  size values range from 128x128 to 1024x1024.
                Large images which require using a disk-based pixel  cache
                benefit  from  large  tile sizes while images which fit in
                memory work well with smaller tile sizes.

           tiff:tile-width=<width>

                Specify the tile width to use while  writing  tiled  TIFF.
                The  tile height is then defaulted to an appropriate size.
                Width should be a multiple of 16. If the value  is  not  a
                multiple  of  16,  then  it will be rounded down.  Enables
                tiled TIFF if it has not already been enabled.

           tiff:tile-height=<height>

                Specify the tile height to use while writing  tiled  TIFF.
                The  tile  width is then defaulted to an appropriate size.
                Height should be a multiple of 16. If the value is  not  a
                multiple  of  16,  then  it will be rounded down.  Enables
                tiled TIFF if it has not already been enabled.

           webp:lossless={true|false}

                Enable lossless encoding.

           webp:method={0-6}

                Quality/speed trade-off.

           webp:image-hint={default,graph,photo,picture}

                Hint for image type.

           webp:target-size=<integer>

                Target size in bytes.

           webp:target-psnr=<float>

                Minimal distortion to try to achieve.

           webp:segments={1-4}

                Maximum number of segments to use.

           webp:sns-strength={0-100}

                Spatial Noise Shaping.

           webp:filter-strength={0-100}

                Filter strength.

           webp:filter-sharpness={0-7}

                Filter sharpness.

           webp:filter-type={0,1}

                Filtering type. 0 = simple,  1  =  strong  (only  used  if
                filter-strength > 0 or autofilter is enabled).

           webp:auto-filter={true|false}

                Auto adjust filter's strength.

           webp:alpha-compression=<integer>

                Algorithm  for  encoding  the  alpha  plane (0 = none, 1 =
                compressed with WebP lossless). Default is 1.

           webp:alpha-filtering=<integer>

                Predictive filtering method for alpha plane. 0:  none,  1:
                fast, 2: best. Default is 1.

           webp:alpha-quality={0-100}

                Between  0  (smallest size) and 100 (lossless). Default is
                100.

           webp:pass=[1..10]

                Number of entropy-analysis passes.

           webp:show-compressed={true|false}

                Export the compressed picture back.  In-loop filtering  is
                not applied.

           webp:preprocessing=[0,1,2]

                0=none, 1=segment-smooth, 2=pseudo-random dithering

           webp:partitions=[0-3]

                log2(number  of token partitions) in [0..3].  Default is 0
                for easier progressive decoding.

           webp:partition-limit={0-100}

                Quality degradation allowed  to  fit  the  512k  limit  on
                prediction  modes  coding (0: no degradation, 100: maximum
                possible degradation).

           webp:emulate-jpeg-size={true|false}

                If true, compression parameters will be remapped to better
                match  the  expected  output  size  from JPEG compression.
                Generally,  the  output  size  will  be  similar  but  the
                degradation will be lower.

           webp:thread-level=<integer>

                If non-zero, try and use multi-threaded encoding.

           webp:low-memory={true|false}

                If set, reduce memory usage (but increase CPU use)

           For  example, to create a postscript file that will render only
           the black pixels of a bilevel image, use:

               gm convert bilevel.tif -define ps:imagemask eps3:stencil.ps

   -delay <1/100ths of a second>
          display the next image after pausing

          This option is useful for  regulating  the  animation  of  image
          sequences  Delay/100  seconds  must expire before the display of
          the next image. The default is no delay between each showing  of
          the image sequence. The maximum delay is 65535.

          You  can  specify  a delay range (e.g. -delay 10-500) which sets
          the minimum and maximum delay.

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the  image  This
          option  specifies the image resolution to store while encoding a
          raster image or the canvas resolution while rendering  (reading)
          vector  formats  such  as  Postscript,  PDF, WMF, and SVG into a
          raster image. Image resolution provides the unit of  measure  to
          apply  when  rendering  to an output device or raster image. The
          default unit of measure is in dots per inch  (DPI).  The  -units
          option may be used to select dots per centimeter instead.
           The default resolution is 72 dots per inch, which is equivalent
          to one point per  pixel  (Macintosh  and  Postscript  standard).
          Computer  screens  are  normally  72  or  96 dots per inch while
          printers typically support 150, 300, 600, or 1200 dots per inch.
          To  determine  the  resolution  of  your display, use a ruler to
          measure the width of your screen in inches, and  divide  by  the
          number  of  horizontal  pixels (1024 on a 1024x768 display).  If
          the file format supports it, this option may be used  to  update
          the  stored  image  resolution.  Note  that Photoshop stores and
          obtains image resolution from a proprietary embedded profile. If
          this profile is not stripped from the image, then Photoshop will
          continue  to  treat  the  image  using  its  former  resolution,
          ignoring  the  image  resolution  specified in the standard file
          header.  The density option is an attribute and does  not  alter
          the  underlying  raster  image.  It  may  be  used to adjust the
          rendered size for desktop publishing purposes by  adjusting  the
          scale  applied  to the pixels. To resize the image so that it is
          the same size at  a  different  resolution,  use  the  -resample
          option.

   -depth <value>
          depth of the image

          This  is  the  number of bits of color to preserve in the image.
          Any value between 1  and  QuantumDepth  (build  option)  may  be
          specified, although 8 or 16 are the most common values. Use this
          option to specify the depth of raw images whose depth is unknown
          such  as GRAY, RGB, or CMYK, or to change the depth of any image
          after it has been read.  The depth  option  is  applied  to  the
          pixels  immediately  so  it  may  be  used  as  a form of simple
          compression by discarding the least significant  bits.  Reducing
          the  depth  in advance may speed up color quantization, and help
          create smaller file sizes when  using  a  compression  algorithm
          like LZW or ZIP.

   -descend
          obtain image by descending window hierarchy

   -despeckle
          reduce the speckles within an image

   -displace <horizontal scale>x<vertical scale>
          shift image pixels as defined by a displacement map

          With this option, composite image is used as a displacement map.
          Black, within  the  displacement  map,  is  a  maximum  positive
          displacement.   White  is  a  maximum  negative displacement and
          middle gray is neutral.  The displacement is scaled to determine
          the  pixel  shift.  By default, the displacement applies in both
          the horizontal and vertical directions.  However, if you specify
          mask,  composite image is the horizontal X displacement and mask
          the vertical Y displacement.

   -display <host:display[.screen]>
          specifies the X server to contact

          This option is used with convert for  obtaining  image  or  font
          from this X server.  See X(1).

   -dispose <method>
          GIF disposal method

          The Disposal Method indicates the way in which the graphic is to
          be treated after being displayed.

          Here are the valid methods:

              Undefined       No disposal specified.
              None            Do not dispose between frames.
              Background      Overwrite the image area with
                              the background color.
              Previous        Overwrite the image area with
                              what was there prior to rendering
                              the image.

   -dissolve <percent>
          dissolve an image into another by the given percent

          The opacity of the composite image is multiplied  by  the  given
          percent, then it is composited over the main image.

   -dither
          apply Floyd/Steinberg error diffusion to the image

          The basic strategy of dithering is to trade intensity resolution
          for spatial resolution by averaging the intensities  of  several
          neighboring  pixels.  Images which suffer from severe contouring
          when reducing colors can be improved with this option.

          The -colors or -monochrome option is required for this option to
          take effect.

          Use  +dither  to  turn  off  dithering  and to render PostScript
          without text or graphic aliasing. Disabling dithering often (but
          not always) leads to decreased processing time.

   -draw <string>
          annotate an image with one or more graphic primitives

          Use  this  option  to annotate an image with one or more graphic
          primitives.     The    primitives    include    shapes,    text,
          transformations, and pixel operations.  The shape primitives are

               point           x,y
               line            x0,y0 x1,y1
               rectangle       x0,y0 x1,y1
               roundRectangle  x0,y0 x1,y1 wc,hc
               arc             x0,y0 x1,y1 a0,a1
               ellipse         x0,y0 rx,ry a0,a1
               circle          x0,y0 x1,y1
               polyline        x0,y0  ...  xn,yn
               polygon         x0,y0  ...  xn,yn
               Bezier          x0,y0  ...  xn,yn
               path            path specification
               image           operator x0,y0 w,h filename

          The text primitive is

               text            x0,y0 string

          The text gravity primitive is

               gravity         NorthWest, North, NorthEast, West, Center,
                               East, SouthWest, South, or SouthEast

          The  text  gravity  primitive only affects the placement of text
          and  does  not  interact  with  the  other  primitives.   It  is
          equivalent to using the -gravity commandline option, except that
          it is limited in scope to the -draw option in which it appears.

          The transformation primitives are

               rotate          degrees
               translate       dx,dy
               scale           sx,sy
               skewX           degrees
               skewY           degrees

          The pixel operation primitives are

               color           x0,y0 method
               matte           x0,y0 method

          The shape primitives are drawn in the  color  specified  in  the
          preceding   -stroke  option.  Except  for  the  line  and  point
          primitives, they are filled with  the  color  specified  in  the
          preceding -fill option.  For unfilled shapes, use -fill none.

          Point requires a single coordinate.

          Line requires a start and end coordinate.

          Rectangle expects an upper left and lower right coordinate.

          RoundRectangle  has  the  upper left and lower right coordinates
          and the width and height of the corners.

          Circle has a center coordinate and a coordinate  for  the  outer
          edge.

          Use  Arc to inscribe an elliptical arc within a rectangle.  Arcs
          require a start and end point as well as the degree of  rotation
          (e.g. 130,30 200,100 45,90).

          Use  Ellipse  to  draw  a  partial ellipse centered at the given
          point with the x-axis and y-axis radius and start and end of arc
          in degrees (e.g. 100,100 100,150 0,360).

          Finally,  polyline and polygon require three or more coordinates
          to define its boundaries.  Coordinates are integers separated by
          an  optional comma.  For example, to define a circle centered at
          100,100 that extends to 150,150 use:

               -draw 'circle 100,100 150,150'

          Paths (See Paths) represent an outline of  an  object  which  is
          defined  in  terms  of  moveto (set a new current point), lineto
          (draw a straight line), curveto (draw  a  curve  using  a  cubic
          Bezier),  arc  (elliptical or circular arc) and closepath (close
          the current  shape  by  drawing  a  line  to  the  last  moveto)
          elements.  Compound  paths  (i.e.,  a  path  with subpaths, each
          consisting of a single moveto followed by one or  more  line  or
          curve  operations)  are possible to allow effects such as "donut
          holes" in objects.

          Use image to composite an image with another image.  Follow  the
          image keyword with the composite operator, image location, image
          size, and filename:

               -draw 'image Over 100,100 225,225 image.jpg'

          You can use 0,0 for the image  size,  which  means  to  use  the
          actual  dimensions found in the image header. Otherwise, it will
          be  scaled  to  the  given  dimensions.   See  -compose  for   a
          description of the composite operators.

          Use  text  to  annotate  an  image  with  text.  Follow the text
          coordinates with a string. If the string  has  embedded  spaces,
          enclose  it  in  single  or  double  quotes.  Optionally you can
          include the image filename, type, width, height, or other  image
          attribute  by  embedding  special format character. See -comment
          for details.

          For example,

               -draw 'text 100,100 "%m:%f %wx%h"'

          annotates the image with MIFF:bird.miff  512x480  for  an  image
          titled bird.miff and whose width is 512 and height is 480.

          If  the  first character of string is @, the text is read from a
          file titled by the remaining characters in the string.

          Rotate rotates subsequent shape primitives and  text  primitives
          about  the  origin  of  the  main  image.  If the -region option
          precedes the -draw option, the origin for transformations is the
          upper left corner of the region.

          Translate translates them.

          Scale scales them.

          SkewX and SkewY skew them with respect to the origin of the main
          image or the region.

          The transformations modify the current affine matrix,  which  is
          initialized  from  the  initial  affine  matrix  defined  by the
          -affine option.  Transformations are cumulative within the -draw
          option.   The initial affine matrix is not affected; that matrix
          is only changed by the appearance of another -affine option.  If
          another  -draw  option  appears,  the  current  affine matrix is
          reinitialized from the initial affine matrix.

          Use color to change the color of a pixel to the fill color  (see
          -fill). Follow the pixel coordinate with a method:

               point
               replace
               floodfill
               filltoborder
               reset

          Consider  the target pixel as that specified by your coordinate.
          The point method recolors the target pixel. The  replace  method
          recolors  any  pixel that matches the color of the target pixel.
          Floodfill recolors any pixel  that  matches  the  color  of  the
          target  pixel  and  is a neighbor, whereas filltoborder recolors
          any neighbor pixel that is not the border color. Finally,  reset
          recolors all pixels.

          Use  matte  to  the change the pixel matte value to transparent.
          Follow the  pixel  coordinate  with  a  method  (see  the  color
          primitive  for  a  description  of  methods).  The  point method
          changes the matte value of the target pixel. The replace  method
          changes  the  matte value of any pixel that matches the color of
          the target pixel. Floodfill changes the matte value of any pixel
          that  matches  the  color of the target pixel and is a neighbor,
          whereas filltoborder changes the matte  value  of  any  neighbor
          pixel  that  is  not  the  border color (-bordercolor).  Finally
          reset changes the matte value of all pixels.

          You can set the primitive color, font,  and  font  bounding  box
          color  with  -fill,  -font,  and  -box respectively. Options are
          processed in command line order so be sure to use these  options
          before the -draw option.

   -edge <radius>
          detect edges within an image

   -emboss <radius>
          emboss an image

   -encoding <type>
          specify the text encoding

          Choose from AdobeCustom, AdobeExpert, AdobeStandard, AppleRoman,
          BIG5, GB2312, Latin 2, None, SJIScode, Symbol, Unicode, Wansung.

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

          MSB indicates big-endian (e.g. SPARC, Motorola  68K)  while  LSB
          indicates  little-endian  (e.g.  Intel 'x86, VAX) byte ordering.
          Native indicates to use the normal ordering for the current CPU.
          This  option currently only influences the CMYK, DPX, GRAY, RGB,
          and TIFF, formats.

          Use +endian to revert to unspecified endianness.

   -enhance
          apply a digital filter to enhance a noisy image

   -equalize
          perform histogram equalization to the image

   -extent <width>x<height>{+-}<x>{+-}<y>
          composite image on background color canvas image

          This option composites the  image  on  a  new  background  color
          (-background)   canvas   image  of  size  <width>x<height>.  The
          existing image content is composited at the  position  specified
          by  geometry  x  and  y offset and/or desired gravity (-gravity)
          using  the  current  image  compose  (-compose)  method.   Image
          content  which  falls  outside  the  bounds  of  the  new  image
          dimensions is discarded.

          For example, this command creates a thumbnail of an  image,  and
          centers  it on a red color backdrop image, offsetting the canvas
          ten pixels to the left and five pixels up, with respect  to  the
          thumbnail:

              gm  convert  infile.jpg  -thumbnail  120x80  -background red
          -gravity center \
                        -extent 140x100-10-5 outfile.jpg

          This command reduces or expands  a  JPEG  image  to  fit  on  an
          800x600 display:

              gm convert -size 800x600 input.jpg \
                        -resize 800x600 -background black \
                        -compose Copy -gravity center \
                        -extent 800x600 \
                        -quality 92 output.jpg

          If  the  aspect ratio of the input image isn't exactly 4:3, then
          the image is centered on an 800x600 black canvas.

   -file <filename>
          write annotated difference image to file

          If -file is specified, then an  annotated  difference  image  is
          generated and written to the specified file. Pixels which differ
          between the reference and compare images are modified from those
          in  the  compare  image  so  that the changed pixels become more
          obvious.   Some  images  may  require  use  of  an   alternative
          highlight  style  (see -highlight-style) or highlight color (see
          -highlight-color) before the changes are obvious.

   -fill <color>
          color to use when filling a graphic primitive

          Colors are represented in GraphicsMagick in the same  form  used
          by SVG. Use "gm convert -list color" to list named colors:

              name               (named color)
              #RGB               (hex numbers, 4 bits each)
              #RRGGBB            (8 bits each)
              #RRRGGGBBB         (12 bits each)
              #RRRRGGGGBBBB      (16 bits each)
              #RGBA              (4 bits each)
              #RRGGBBAA          (8 bits each)
              #RRRGGGBBBAAA      (12 bits each)
              #RRRRGGGGBBBBAAAA  (16 bits each)
              rgb(r,g,b)         (r,g,b are decimal numbers)
              rgba(r,g,b,a)      (r,g,b,a are decimal numbers)

          Enclose  the  color  specification in quotation marks to prevent
          the "#" or the parentheses from being interpreted by your shell.

          For example,

              gm convert -fill blue ...
              gm convert -fill "#ddddff" ...
              gm convert -fill "rgb(65000,65000,65535)" ...

          The shorter forms are scaled up, if  necessary  by  replication.
          For   example,   #3af,   #33aaff,   and  #3333aaaaffff  are  all
          equivalent.

          See -draw for further details.

   -filter <type>
          use this type of filter when resizing an image

          Use this option to affect the resizing  operation  of  an  image
          (see   -geometry).    Choose  from  these  filters  (ordered  by
          approximate increasing CPU time):

               Point
               Box
               Triangle
               Hermite
               Hanning
               Hamming
               Blackman
               Gaussian
               Quadratic
               Cubic
               Catrom
               Mitchell
               Lanczos
               Bessel
               Sinc

          The default filter is automatically selected to provide the best
          quality  while  consuming  a  reasonable  amount  of  time.  The
          Mitchell filter  is  used  if  the  image  supports  a  palette,
          supports  a  matte  channel, or is being enlarged, otherwise the
          Lanczos filter is used.

   -flatten
          flatten a sequence of images

          In some file formats (e.g. Photoshop's PSD) complex  images  may
          be  represented  by  "layers" (independent images) which must be
          composited in order to obtain the final rendition.  The -flatten
          option accomplishes this composition.  The sequence of images is
          replaced by a single image created by compositing each image  in
          turn,  while  respecting composition operators and page offsets.
          While -flatten is immediately useful for eliminating layers,  it
          is also useful as a general-purpose composition tool.

          The  sequence  of  images is terminated by the appearance of any
          option.  If the -flatten option appears after all of  the  input
          images,  all  images  are  flattened.  Also see -mosaic which is
          similar to -flatten except that it adds a suitably-sized  canvas
          base image.

          For  example,  this  composites  an  image  on  top of a 640x400
          transparent black canvas image:

              gm convert -size 640x300 xc:transparent \
                        -compose over -page +0-100 \
                        frame.png -flatten output.png

          and this flattens a Photoshop PSD file:

              gm convert input.psd -flatten output.png

   -flip  create a "mirror image"

          reflect the scanlines in the vertical direction.

   -flop  create a "mirror image"

          reflect the scanlines in the horizontal direction.

   -font <name>
          use this font when annotating the image with text

          You can tag a font  to  specify  whether  it  is  a  PostScript,
          TrueType,  or  X11  font.   For example, Arial.ttf is a TrueType
          font, ps:helvetica is PostScript, and x:fixed is X11.

   -foreground <color>
          define the foreground color

          The color is specified using  the  format  described  under  the
          -fill option.

   -format <type>
          the image format type

          When used with the mogrify utility, this option will convert any
          image to the image format you  specify.   See  GraphicsMagick(1)
          for a list of image format types supported by GraphicsMagick, or
          see the output of 'gm -list format'.

          By default the file is written to its original  name.   However,
          if  the  filename  extension  matches  a  supported  format, the
          extension is replaced with the image format type specified  with
          -format.   For  example,  if you specify tiff as the format type
          and the input image filename  is  image.gif,  the  output  image
          filename becomes image.tiff.

   -format <string>
          output formatted image characteristics

          When used with the identify utility, or the convert utility with
          output written to the  'info:-'  file  specification,  use  this
          option  to print information about the image in a format of your
          choosing.  You can include  the  image  filename,  type,  width,
          height,  Exif  data,  or  other  image  attributes  by embedding
          special format characters:

               %b   file size
               %c   comment
               %d   directory
               %e   filename extension
               %f   filename
               %g   page dimensions and offsets
               %h   height
               %i   input filename
               %k   number of unique colors
               %l   label
               %m   magick
               %n   number of scenes
               %o   output filename
               %p   page number
               %q   image bit depth
               %r   image type description
               %s   scene number
               %t   top of filename
               %u   unique temporary filename
               %w   width
               %x   horizontal resolution
               %y   vertical resolution
               %A   transparency supported
               %C   compression type
               %D   GIF disposal method
               %G   Original width and height
               %H   page height
               %M   original filename specification
               %O   page offset (x,y)
               %P   page dimensions (width,height)
               %Q   compression quality
               %T   time delay (in centi-seconds)
               %U   resolution units
               %W   page width
               %X   page horizontal offset (x)
               %Y   page vertical offset (y)
               %@   trim bounding box
               %#   signature
               \n   newline
               \r   carriage return
               %%   %

          For example,

               -format "%m:%f %wx%h"

          displays MIFF:bird.miff 512x480 for an  image  titled  bird.miff
          and whose width is 512 and height is 480.

          If the first character of string is @, the format is read from a
          file titled by the remaining characters in the string.

          The values of image type (%p) which may be returned include:

               Bilevel
               Grayscale
               GrayscaleMatte
               Palette
               PaletteMatte
               TrueColor
               TrueColorMatte
               ColorSeparation
               ColorSeparationMatte
               Optimize

          You can also use the  following  special  formatting  syntax  to
          print Exif information contained in the file:

               %[EXIF:<tag>]

          Where "<tag>" may be one of the following:

               *  (print all Exif tags, in keyword=data format)
               !  (print all Exif tags, in tag_number format)
               #hhhh (print data for Exif tag #hhhh)
               ImageWidth
               ImageLength
               BitsPerSample
               Compression
               PhotometricInterpretation
               FillOrder
               DocumentName
               ImageDescription
               Make
               Model
               StripOffsets
               Orientation
               SamplesPerPixel
               RowsPerStrip
               StripByteCounts
               XResolution
               YResolution
               PlanarConfiguration
               ResolutionUnit
               TransferFunction
               Software
               DateTime
               Artist
               WhitePoint
               PrimaryChromaticities
               TransferRange
               JPEGProc
               JPEGInterchangeFormat
               JPEGInterchangeFormatLength
               YCbCrCoefficients
               YCbCrSubSampling
               YCbCrPositioning
               ReferenceBlackWhite
               CFARepeatPatternDim
               CFAPattern
               BatteryLevel
               Copyright
               ExposureTime
               FNumber
               IPTC/NAA
               ExifOffset
               InterColorProfile
               ExposureProgram
               SpectralSensitivity
               GPSInfo
               ISOSpeedRatings
               OECF
               ExifVersion
               DateTimeOriginal
               DateTimeDigitized
               ComponentsConfiguration
               CompressedBitsPerPixel
               ShutterSpeedValue
               ApertureValue
               BrightnessValue
               ExposureBiasValue
               MaxApertureValue
               SubjectDistance
               MeteringMode
               LightSource
               Flash
               FocalLength
               MakerNote
               UserComment
               SubSecTime
               SubSecTimeOriginal
               SubSecTimeDigitized
               FlashPixVersion
               ColorSpace
               ExifImageWidth
               ExifImageLength
               InteroperabilityOffset
               FlashEnergy
               SpatialFrequencyResponse
               FocalPlaneXResolution
               FocalPlaneYResolution
               FocalPlaneResolutionUnit
               SubjectLocation
               ExposureIndex
               SensingMethod
               FileSource
               SceneType

          JPEG  specific  information  (from  reading  a JPEG file) may be
          obtained like this:

               %[JPEG-<tag>]

          Where "<tag>" may be one of the following:

               *                 (all JPEG-related tags, in
                                  keyword=data format)
               Quality           IJG JPEG "quality" estimate
               Colorspace        JPEG colorspace numeric ID
               Colorspace-Name   JPEG colorspace name
               Sampling-factors  JPEG sampling factors

          Please note that JPEG has no notion of "quality"  and  that  the
          quality  metric  used by, and estimated by the software is based
          on the  quality  metric  established  by  IJG  JPEG  6b.   Other
          encoders  (e.g.  that  used  by  Adobe  Photoshop) use different
          encoding metrics.

          Surround  the  format  specification  with  quotation  marks  to
          prevent  your  shell  from misinterpreting any spaces and square
          brackets.

   -frame <width>x<height>+<outer bevel width>+<inner bevel width>
          surround the image with an ornamental border

          See -geometry for details about the geometry specification.  The
          -frame option is not affected by the -gravity option.

          The  color  of  the  border  is  specified  with the -mattecolor
          command line option.

   -frame include the X window frame in the imported image

   -fuzz <distance>{%}
          colors within this Euclidean distance are considered equal

          A number of algorithms search for a target color. By default the
          color  must  be  exact. Use this option to match colors that are
          close (in Euclidean distance) to the  target  color  in  RGB  3D
          space.  For example, if you want to automatically trim the edges
          of an image with -trim but the image was scanned and the  target
          background  color  may differ by a small amount. This option can
          account for these differences.

          The distance can be in absolute intensity units or, by appending
          "%",  as  a  percentage  of the maximum possible intensity (255,
          65535, or 4294967295).

   -gamma <value>
          level of gamma correction

          The same color image displayed on two different workstations may
          look  different  due  to differences in the display monitor. Use
          gamma correction to adjust for this color difference. Reasonable
          values  extend  from 0.8 to 2.3. Gamma less than 1.0 darkens the
          image and gamma greater than 1.0 lightens it. Large  adjustments
          to  image gamma may result in the loss of some image information
          if the pixel quantum size is only eight bits (quantum range 0 to
          255).

          You  can apply separate gamma values to the red, green, and blue
          channels of the image with a gamma  value  list  delimited  with
          slashes (e.g., 1.7/2.3/1.2).

          Use  +gamma  value to set the image gamma level without actually
          adjusting the image pixels. This option is useful if  the  image
          is  of a known gamma but not set as an image attribute (e.g. PNG
          images).

   -gaussian <radius>{x<sigma>}
          blur the image with a Gaussian operator

          Use the given radius and standard deviation (sigma).

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

          The -geometry option is used for a number of different purposes,
          depending  on  the  utility  it  is  used with.  <pp For the X11
          commands ('animate', 'display', and 'import'), it specifies  the
          preferred  size  and  location of the Image window.  By default,
          the window size is the image size and the location is chosen  by
          you (or your window manager) when it is mapped.
           For  the 'import', 'convert', 'mogrify' utility commands it may
          be used to specify the desired size when resizing an image.   In
          this  case,  symbols representing resize options may be appended
          to the geometry string to influence how the  resize  request  is
          treated.

          See  later  notes corresponding to usage by particular commands.
          The following notes apply to when -geometry is used to express a
          resize  request,  taking  into account the current properties of
          the image.

          By default, the width and height are maximum  values.  That  is,
          the  image is expanded or contracted to fit the width and height
          value while maintaining the aspect ratio of the image.

          Append a ^ to the geometry so that the image  is  resized  while
          maintaining  the  aspect  ratio  of the image, but the resulting
          width or height  are  treated  as  minimum  values  rather  than
          maximum values.

          Append  an  exclamation point to the geometry to force the image
          size to exactly the  size  you  specify.  For  example,  if  you
          specify 640x480! the image width is set to 640 pixels and height
          to 480.

          If only the width is specified, without the trailing  'x',  then
          height  is  set  to  width  (e.g.,  -geometry 100 is the same as
          -geometry 100x100).  If only the width is specified but with the
          trailing  'x',  then  width  assumes the value and the height is
          chosen to maintain the aspect ratio of the image.  Similarly, if
          only  the  height  is specified prefixed by 'x' (e.g., -geometry
          x256), the width is chosen to maintain the aspect ratio.

          To specify a percentage width or height instead, append  %.  The
          image  size is multiplied by the width and height percentages to
          obtain the final image dimensions. To increase the  size  of  an
          image,  use a value greater than 100 (e.g. 125%). To decrease an
          image's size, use a percentage less than 100.

          Use @ to specify the maximum area in pixels of an image.

          Use > to change the dimensions of the image only if its width or
          height  exceeds  the geometry specification. < resizes the image
          only if both of  its  dimensions  are  less  than  the  geometry
          specification.  For  example,  if you specify '640x480>' and the
          image size is 256x256, the image size does not change.  However,
          if  the image is 512x512 or 1024x1024, it is resized to 480x480.
          Enclose the geometry specification in quotation marks to prevent
          the  <  or  >  from  being  interpreted  by your shell as a file
          redirection.

          When used with animate and display, offsets are handled  in  the
          same  manner as in X(1) and the -gravity option is not used.  If
          the x is negative, the offset  is  measured  leftward  from  the
          right  edge  of  the screen to the right edge of the image being
          displayed.  Similarly, negative y is measured between the bottom
          edges.   The  offsets  are  not affected by "%"; they are always
          measured in pixels.

          When used as a composite option, -geometry gives the  dimensions
          of  the  image  and  its  location with respect to the composite
          image.  If the -gravity option is present with NorthEast,  East,
          or  SouthEast  gravity,  the  x represents the distance from the
          right edge of the image to  the  right  edge  of  the  composite
          image.   Similarly,  if  the  -gravity  option  is  present with
          SouthWest, South, or SouthEast gravity, y  is  measured  between
          the  bottom  edges.  Accordingly,  a  positive offset will never
          point in the direction outside of the image.   The  offsets  are
          not  affected  by  "%";  they are always measured in pixels.  To
          specify the dimensions of the composite image, use  the  -resize
          option.

          When  used  as a convert, import or mogrify option, -geometry is
          synonymous with -resize and specifies the  size  of  the  output
          image.  The offsets, if present, are ignored.

          When  used  as  a  montage option, -geometry specifies the image
          size and border size for  each  tile;  default  is  256x256+0+0.
          Negative  offsets  (border  dimensions)  are  meaningless.   The
          -gravity option affects the placement of the  image  within  the
          tile;  the  default  gravity for this purpose is Center.  If the
          "%" sign appears in the geometry specification, the tile size is
          the specified percentage of the original dimensions of the first
          tile.  To specify the dimensions of the montage, use the -resize
          option.

   -gravity <type>
          direction primitive  gravitates to when annotating the image.

          Choices  are:  NorthWest,  North, NorthEast, West, Center, East,
          SouthWest, South, SouthEast.

          The direction you choose specifies where to  position  the  text
          when annotating the image. For example Center gravity forces the
          text to be centered within the  image.  By  default,  the  image
          gravity  is NorthWest.  See -draw for more details about graphic
          primitives.  Only the text primitive is affected by the -gravity
          option.

          The  -gravity  option is also used in concert with the -geometry
          option and other options that take <geometry>  as  a  parameter,
          such  as the -crop option.  See -geometry for details of how the
          -gravity option interacts with the <x> and <y> parameters  of  a
          geometry specification.

          When  used  as  an  option  to  composite,  -gravity  gives  the
          direction that the image gravitates within the composite.

          When used as an option to montage, -gravity gives the  direction
          that  an image gravitates within a tile.  The default gravity is
          Center for this purpose.

   -green-primary <x>,<y>
          green chromaticity primary point

   -hald-clut <clut>
          apply a Hald CLUT to the image

          A Hald CLUT ("Color Look-Up Table") is a  special  square  color
          image  which  contains a look-up table for red, green, and blue.
          The size of the Hald CLUT image is determined by its order.  The
          width (and height) of a Hald CLUT is the cube of the order.  For
          example, a Hald CLUT of  order  8  is  512x512  pixels  (262,144
          colors)  and  of  order  16 is 4096x4096 (16,777,216 colors).  A
          special CLUT is the identity CLUT which which causes  no  change
          to the input image.  In order to use the Hald CLUT, one takes an
          identity CLUT and adjusts its colors in some way.  The  modified
          CLUT  can  then  be used to transform any number of images in an
          identical way.

          GraphicsMagick contains a built-in identity CLUT  generator  via
          the  IDENTITY  coder.   For  example  reading from the file name
          IDENTITY:8 returns an identity CLUT of order  8.   Typical  Hald
          CLUT  identity  images  have  an order of between 8 and 16.  The
          default  order  for  the   IDENTITY   CLUT   generator   is   8.
          Interpolation  is  used  so it is not usually necessary for CLUT
          images to be very large.  The  PNG  file  format  is  ideal  for
          storing Hald CLUT images because it compresses them very well.

   -help  print usage instructions

   -highlight-color <color>
          pixel annotation color

          Specifies the color to use when annotating difference pixels.

   -highlight-style <style>
          pixel annotation style

          Specifies  the  pixel  difference  annotation style used to draw
          attention to changed pixels. May be one  of  Assign,  Threshold,
          Tint, or XOR; where Assign replaces the pixel with the highlight
          color (see -highlight-color), Threshold replaces the pixel  with
          black  or white based on the difference in intensity, Tint alpha
          tints the pixel with the highlight color, and XOR  does  an  XOR
          between the pixel and the highlight color.

   -iconGeometry <geometry>
          specify the icon geometry

          Offsets,  if  present in the geometry specification, are handled
          in the same manner as the -geometry option, using X11  style  to
          handle negative offsets.

   -iconic
          iconic animation

   -immutable
          make image immutable

   -implode <factor>
          implode image pixels about the center

   -intent <type>
          use this type of rendering intent when managing the image color

          Use  this option to affect the the color management operation of
          an image (see -profile).  Choose from these  intents:  Absolute,
          Perceptual, Relative, Saturation.

          The default intent is undefined.

   -interlace <type>
          the type of interlacing scheme

          Choices  are:  None,  Line,  Plane, or Partition. The default is
          None.

          This option is used to specify the type  of  interlacing  scheme
          for  raw  image  formats  such as RGB or YUV.  None means do not
          interlace (RGBRGBRGBRGBRGBRGB...),

          Line            uses            scanline             interlacing
          (RRR...GGG...BBB...RRR...GGG...BBB...),  and  Plane  uses  plane
          interlacing (RRRRRR...GGGGGG...BBBBBB...).

          Partition is like plane except the different planes are saved to
          individual files (e.g. image.R, image.G, and image.B).

          Use Line to create an interlaced PNG or  GIF or progressive JPEG
          image.

   -label <name>
          assign a label to an image

          Use this option to assign a specific label to  the  image,  when
          writing  to  an image format that supports labels, such as TIFF,
          PNG,  MIFF,  or  PostScript.  You  can  include  the  the  image
          filename,  type,  width,  height,  or  other  image attribute by
          embedding special format character.  A label is not drawn on the
          image, but is embedded in the image datastream via a "Label" tag
          or similar mechanism.  If you want the label to  be  visible  on
          the  image  itself,  use  the  -draw  option.   See -comment for
          details.

          For example,

               -label "%m:%f %wx%h"

          produces an image label of MIFF:bird.miff 512x480 for  an  image
          titled bird.miff and whose width is 512 and height is 480.

          If  the  first character of string is @, the image label is read
          from a file titled by the remaining characters in the string.

          When converting to PostScript, use  this  option  to  specify  a
          header  string  to print above the image. Specify the label font
          with -font.

          When creating a montage, by default the label associated with an
          image  is  displayed with the corresponding tile in the montage.
          Use the +label option to suppress this behavior.

   -lat <width>x<height>{+-}<offset>{%}
          perform local adaptive thresholding

          Perform local adaptive thresholding using the  specified  width,
          height,  and  offset.   The offset is a distance in sample space
          from the mean, as an absolute integer  ranging  from  0  to  the
          maximum  sample value or as a percentage.  If the percent option
          is supplied, then the offset is computed as a percentage of  the
          quantum  range.   It  is strongly recommended to use the percent
          option so that results are not sensitive to pixel quantum depth.

          For example,

               -colorspace gray -lat "10x10-5%"

          will  help  clarify  a  scanned  grayscale  or  color  document,
          producing a bi-level equivalent.

   -level <black_point>{,<gamma>}{,<white_point>}{%}
          adjust the level of image contrast

          Give  one,  two  or  three  values delimited with commas: black-
          point, gamma, white-point (e.g. 10,1.0,250 or  2%,0.5,98%).  The
          black and white points range from 0 to MaxRGB or from 0 to 100%;
          if the white point is omitted it is set  to  MaxRGB-black_point.
          If  a  "%" sign is present anywhere in the string, the black and
          white points are percentages of MaxRGB.  Gamma  is  an  exponent
          that  ranges  from  0.1 to 10.; if it is omitted, the default of
          1.0 (no gamma  correction)  is  assumed.  This  interface  works
          similar  to  Photoshop's "Image->Adjustments->Levels..."  "Input
          Levels" interface.

   -limit <type> <value>
          Disk, File,  Map,  Memory,  Pixels,  Width,  Height  or  Threads
          resource limit

          By default, resource limits are estimated based on the available
          resources of the system. The resource limits are  Disk,  maximum
          total   disk  space  consumed;  File,  maximum  number  of  file
          descriptors allowed to be  open  at  once;  Map,  maximum  total
          number of file bytes which may be memory mapped; Memory, maximum
          total number of bytes of heap memory  used  for  image  storage;
          Pixels,  maximum absolute image size (per image); Width, maximum
          image pixels width; Height, maximum  image  pixels  height;  and
          Threads,  the maximum number of worker threads to use per OpenMP
          thread team.

          These resource limits are used to decide if (for a given  image)
          the  decoded  image  ("pixel  cache")  should  be stored in heap
          memory (RAM), in a memory-mapped disk file, or in  a  disk  file
          accessed  via read/write I/O.  The number of total pixels in one
          image, and/or the width/height, may also be limited in order  to
          force  the  reading, or creation of images larger than the limit
          (in pixels) to intentionally fail. The disk limit establishes an
          overall  limit since using the disk is the means of last resort.
          When the disk limit has been reached,  no  more  images  may  be
          read.

          The  value  argument is an absolute value, but may have standard
          binary suffix characters applied ('K', 'M', 'G', 'T', 'P',  'E')
          to apply a scaling to the value (based on a multiplier of 1024).
          Any additional characters  are  ignored.  For  example,  '-limit
          Pixels  10MP' limits the maximum image size to 10 megapixels and
          '-limit memory 32MB -limit map 64MB' limits  memory  and  memory
          mapped files to 32 megabytes and 64 megabytes respectively.

          Resource limits may also be set using environment variables. The
          environment  variables  MAGICK_LIMIT_DISK,   MAGICK_LIMIT_FILES,
          MAGICK_LIMIT_MAP,    MAGICK_LIMIT_MEMORY,   MAGICK_LIMIT_PIXELS,
          MAGICK_LIMIT_WIDTH, MAGICK_LIMIT_HEIGHT,and OMP_NUM_THREADS  may
          be  used  to  set  the limits for disk space, open files, memory
          mapped size, heap memory, per-image pixels, image  width,  image
          height, and threads respectively.

          Use the option -list resource list the current limits.

   -linewidth
          the line width for subsequent draw operations

   -list <type>
          the type of list

          Choices  are:  Color, Delegate, Format, Magic, Module, Resource,
          or Type. The Module option is only available  if  GraphicsMagick
          was built to support loadable modules.

          This   option   lists   information   about  the  GraphicsMagick
          configuration.

   -log <string>
          Specify format for debug log

          This option specifies the format for the log  printed  when  the
          -debug option is active.

          You  can  display  the following components by embedding special
          format characters:

               %d   domain
               %e   event
               %f   function
               %l   line
               %m   module
               %p   process ID
               %r   real CPU time
               %t   wall clock time
               %u   user CPU time
               %%   percent sign
               \n   newline
               \r   carriage return

          For example:

              gm convert -debug coders -log "%u %m:%l %e" in.gif out.png

          The default behavior is to print all of the components.

   -loop <iterations>
          add Netscape loop extension to your GIF animation

          A value other than zero forces the animation to repeat itself up
          to iterations times.

   -magnify
          magnify the image

          The image size is doubled using linear interpolation.

   -magnify <factor>
          magnify the image

          The displayed image is magnified by factor.

   -map <filename>
          choose a particular set of colors from this image

          [convert or mogrify]

          By  default,  color  reduction  chooses an optimal set of colors
          that best represent the original image. Alternatively,  you  can
          choose  a  particular set of colors from an image file with this
          option.

          Use +map to reduce all images in the image sequence that follows
          to  a  single  optimal set of colors that best represent all the
          images.  The sequence of images is terminated by the  appearance
          of  any  option.   If  the  +map option appears after all of the
          input images, all images are mapped.

   -map <type>
          display image using this type.

          [animate or display]

          Choose from these Standard Colormap types:

               best
               default
               gray
               red
               green
               blue

          The X server must support  the  Standard  Colormap  you  choose,
          otherwise  an  error  occurs.  Use  list as the type and display
          searches the list of colormap types in top-to-bottom order until
          one is located. See xstdcmap(1) for one way of creating Standard
          Colormaps.

   -mask <filename>
          Specify a clipping mask

          The image read from the file is used as  a  clipping  mask.   It
          must have the same dimensions as the image being masked.

          If  the  mask  image contains an opacity channel, the opacity of
          each pixel is used to define the mask.  Otherwise, the intensity
          (gray level) of each pixel is used.  Unmasked (black) pixels are
          modified while masked pixels  (not  black)  are  protected  from
          alteration.

          Use +mask to remove the clipping mask.

          It  is not necessary to use -clip to activate the mask; -clip is
          implied by -mask.

   -matte store matte channel if the image has one

          If the image does not have a matte  channel,  create  an  opaque
          one.

          Use  +matte  to  ignore the matte channel and to avoid writing a
          matte channel in the output file.

   -mattecolor <color>
          specify the color to be used with the -frame option

          The color is specified using  the  format  described  under  the
          -fill option.

   -maximum-error <limit>
          specifies the maximum amount of total image error

          Specifies  the  maximum  amount  of  total image error (based on
          comparison using a specified metric)  before  an  error  ("image
          difference  exceeds  limit") is reported.  The error is reported
          via a non-zero command execution return status.

   -median <radius>
          apply a median filter to the image

   -metric <metric>
          comparison metric (MAE, MSE, PAE, PSNR, RMSE)

   -minify <factor>
          minify the image

          The image size is halved using linear interpolation.

   -mode <value>
          mode of operation

          The available montage modes are frame to place the images  in  a
          rectangular   grid   while   adding   a  decorative  frame  with
          dropshadow, unframe to place undecorated images in a rectangular
          grid,  and  concatenate  to  pack  the  images  closely together
          without any well-defined grid or decoration.

   -modulate brightness[,saturation[,hue]]
          vary the brightness, saturation, and hue of an image

          Specify the percent change in brightness, color saturation,  and
          hue  separated  by  commas.  Default  argument  values  are  100
          percent, resulting in no change. For example,  to  increase  the
          color brightness by 20% and decrease the color saturation by 10%
          and leave the hue unchanged, use: -modulate 120,90.

          Hue is the percentage of  absolute  rotation  from  the  current
          position. For example 50 results in a counter-clockwise rotation
          of 90 degrees,  150  results  in  a  clockwise  rotation  of  90
          degrees,  with  0  and  200  both resulting in a rotation of 180
          degrees.

   -monitor
          show progress indication

          A simple command-line progress indication  is  shown  while  the
          command  is  running. The process indication shows the operation
          currently being performed and the  percent  completed.  Commands
          using  X11 may replace the command line progress indication with
          a graphical one once an image has been displayed.

   -monochrome
          transform the image to black and white

   -morph <frames>
          morphs an image sequence

          Both the image pixels and size are linearly interpolated to give
          the appearance of a meta-morphosis from one image to the next.

          The  sequence  of  images is terminated by the appearance of any
          option.  If the -morph option appears after  all  of  the  input
          images, all images are morphed.

   -mosaic
          create a mosaic from an image or an image sequence

          The  -mosaic  option provides a flexible way to composite one or
          more images onto a solid-color canvas image. It works similar to
          -flatten  except  that  a  base  canvas  image  is automatically
          created  with  a  suitable  size  given  the  image  size,  page
          dimensions,  and  page  offsets of images to be composited.  The
          color of the base canvas image may be set  via  the  -background
          option.   The  default  canvas  color is 'white', but 'black' or
          'transparent' may be more suitable depending on the  composition
          algorithm requested.

          The  -compose  option  may  be  used  to specify the composition
          algorithm to use when compositing the subsequent  image  on  the
          base canvas.

          The  -page option can be used to establish the dimensions of the
          mosaic and to position the subsequent image within  the  mosaic.
          If  the  -page  argument does not specify width and height, then
          the canvas dimensions are evaluated based on the image sizes and
          offsets.

          The  sequence  of  images is terminated by the appearance of any
          option.  If the -mosaic option appears after all  of  the  input
          images, all images are included in the mosaic.

          The  following is an example of composing an image based on red,
          green, and blue layers extracted from a sequence of  images  and
          pasted on the canvas image at specified offsets:

              gm convert -background black \
                        -compose CopyRed   -page +0-100 red.png \
                        -compose CopyGreen -page +0+40  green.png \
                        -compose CopyBlue  -page +0+180 blue.png \
                        -mosaic output.png

   -motion-blur <radius>{x<sigma>}{+angle}
          Simulate motion blur

          Simulate  motion  blur  by  convolving the image with a Gaussian
          operator of the given radius and standard deviation (sigma). For
          reasonable  results,  radius  should  be  larger  than sigma. If
          radius is zero, then a suitable radius is automatically selected
          based on sigma. The angle specifies the angle that the object is
          coming from (side which is blurred).

   -name  name an image

   -negate
          replace every pixel with its complementary color

          The red, green, and blue intensities of an  image  are  negated.
          White  becomes  black, yellow becomes blue, etc.  Use +negate to
          only negate the grayscale pixels of the image.

   -noise <radius|type>
          add or reduce noise in an image

          The principal function of noise peak elimination  filter  is  to
          smooth   the   objects  within  an  image  without  losing  edge
          information  and  without  creating  undesired  structures.  The
          central  idea  of  the  algorithm is to replace a pixel with its
          next neighbor in value within a pixel window, if this pixel  has
          been  found to be noise. A pixel is defined as noise if and only
          if this pixel is a maximum or minimum within the pixel window.

          Use radius to specify the width of the neighborhood.

          Use +noise followed by a noise type to add noise  to  an  image.
          The noise added modulates the existing image pixels. Choose from
          these noise types:

               Uniform
               Gaussian
               Multiplicative
               Impulse
               Laplacian
               Poisson
               Random (uniform distribution)

   -noop  NOOP (no option)

          The -noop option can be used to terminate a group of images  and
          reset  all options to their default values, when no other option
          is desired.

   -normalize
          transform image to span the full range of color values

          This is a contrast enhancement  technique  based  on  the  image
          histogram.

          When  computing  the  contrast enhancement values, the histogram
          edges are truncated so that the majority of the image pixels are
          considered  in  the  constrast  enhancement,  and outliers (e.g.
          random noise or minute details) are  ignored.   The  default  is
          that  0.1  percent  of  the  histogram entries are ignored.  The
          percentage of the histogram to ignore may be specified by  using
          the  -set  option with the histogram-threshold parameter similar
          to -set histogram-threshold 0.01 to specify 0.01 percent.  Use 0
          percent  to  use  the entire histogram, with possibly diminished
          contrast enhancement.

   -opaque <color>
          change this color to the pen color within the image

          The color is specified using  the  format  described  under  the
          -fill  option.   The color is replaced if it is identical to the
          target color, or close enough to the target color in a 3D  space
          as defined by the Euclidean distance specified by -fuzz.

          See -fill and -fuzz for more details.

   -operator channel operator rvalue[%]
          apply  a  mathematical,  bitwise,  or value operator to an image
          channel

          Apply a low-level mathematical, bitwise, or value operator to  a
          selected  image  channel or all image channels. Operations which
          result in negative results are reset  to  zero,  and  operations
          which  overflow  the  available  range  are reset to the maximum
          possible value.

          Select a channel from: Red, Green, Blue, Opacity,  Matte,  Cyan,
          Magenta,  Yellow,  Black,  All,  or  Gray. All only modifies the
          color channels and does not modify the Opacity  channel.  Except
          for  the  threshold  operators,  All  operates  on  each channel
          independently so that operations are on a per-channel basis.

          Gray treats the color channels  as  a  grayscale  intensity  and
          performs   the  requested  operation  on  the  equivalent  pixel
          intensity so the result is a gray  image.   Select  an  operator
          from  Add,  And,  Assign,  Depth, Divide, Gamma, Negate, LShift,
          Log, Max, Min, Multiply, Or, Pow  RShift,  Subtract,  Threshold,
          Threshold-White,     Threshold-White-Negate,    Threshold-Black,
          Threshold-Black-Negate,  Xor,   Noise-Gaussian,   Noise-Impulse,
          Noise-Laplacian,   Noise-Multiplicative,  Noise-Poisson,  Noise-
          Random, and Noise-Uniform.

          Rvalue may be any floating  point  or  integer  value.  Normally
          rvalue  will be in the range of 0 to MaxRGB, where MaxRGB is the
          largest quantum value  supported  by  the  GraphicsMagick  build
          (255,  65535,  or  4294967295) but values outside this range are
          useful for some arithmetic operations.  Arguments to logical  or
          bit-wise  operations  are  rounded  to a positive integral value
          prior to use. If  a  percent  (%)  symbol  is  appended  to  the
          argument, then the argument has a range of 0 to 100 percent.

          The following is a description of the operators:

           Add

                Result is rvalue added to channel value.

           And

                Result is the logical AND of rvalue with channel value.

           Assign

                Result is rvalue.

           Depth

                Result  is  channel  value  adjusted  so  that  it  may be
                (approximately) stored in the  specified  number  of  bits
                without additional loss.

           Divide

                Result is channel value divided by rvalue.

           Gamma

                Result is channel value gamma adjusted by rvalue.

           LShift

                Result  is  channel  value  bitwise left shifted by rvalue
                bits.

           Log

                Result is computed as log(value*rvalue+1)/log(rvalue+1).

           Max

                Result is assigned to rvalue if  rvalue  is  greater  than
                value.

           Min

                Result is assigned to rvalue if rvalue is less than value.

           Multiply

                Result is channel value multiplied by rvalue.

           Negate

                Result is inverse of channel value (like a film negative).
                An rvalue must be supplied  but  is  currently  not  used.
                Inverting the image twice results in the original image.

           Or

                Result is the logical OR of rvalue with channel value.

           Pow

                Result  is computed as pow(value,rvalue). Similar to Gamma
                except that rvalue is not inverted.

           RShift

                Result is channel value bitwise right  shifted  by  rvalue
                bits.

           Subtract

                Result is channel value minus rvalue.

           Threshold

                Result is maximum (white) if channel value is greater than
                rvalue, or minimum (black) if it is less than or equal  to
                rvalue.  If  all channels are specified, then thresholding
                is done based on computed pixel intensity.

           Threshold-white

                Result is maximum (white) if channel value is greater than
                rvalue  and  is  unchanged  if it is less than or equal to
                rvalue. This can be used to remove apparent noise from the
                bright  parts  of an image. If all channels are specified,
                then  thresholding  is  done  based  on   computed   pixel
                intensity.

           Threshold-White-Negate

                Result  is  set  to black if channel value is greater than
                rvalue and is unchanged if it is less  than  or  equal  to
                rvalue.  If  all channels are specified, then thresholding
                is done based on computed pixel intensity.

           Threshold-black

                Result is minimum (black) if channel value  is  less  than
                than  rvalue  and  is  unchanged  if it is greater than or
                equal to rvalue. This can be used to remove apparent noise
                from  the  dark  parts  of  an  image. If all channels are
                specified, then thresholding is  done  based  on  computed
                pixel intensity.

           Threshold-Black-Negate

                Result  is set to white if channel value is less than than
                rvalue and is unchanged if it is greater than or equal  to
                rvalue.  If  all channels are specified, then thresholding
                is done based on computed pixel intensity.

           Xor

                Result is the logical XOR of rvalue with channel value. An
                interesting  property  of  XOR is that performing the same
                operation twice results in the original value.

           Noise-Gaussian

                Result  is  the  current  channel  value  modulated   with
                gaussian  noise  according  to  the intensity specified by
                rvalue.

           Noise-Impulse

                Result is the current channel value modulated with impulse
                noise according to the intensity specified by rvalue.

           Noise-Laplacian

                Result   is  the  current  channel  value  modulated  with
                laplacian noise according to the  intensity  specified  by
                rvalue.

           Noise-Multiplicative

                Result   is  the  current  channel  value  modulated  with
                multiplicative gaussian noise according to  the  intensity
                specified by rvalue.

           Noise-Poisson

                Result is the current channel value modulated with poisson
                noise according to the intensity specified by rvalue.

           Noise-Random

                Result is the current channel value modulated with  random
                (uniform  distribution)  noise  according to the intensity
                specified  by  rvalue.   The   initial   noise   intensity
                (rvalue=1.0) is the range of one pixel quantum span.

           Noise-Uniform

                Result  is  the  channel  value with uniform noise applied
                according to the intensity specified by rvalue.

           As an example, the Assign operator assigns a fixed value  to  a
           channel.  For example, this command sets the red channel to the
           mid-range value:

               gm convert in.bmp -operator red assign "50%" out.bmp

           The following applies 50% thresholding to the image and returns
           a gray image:

               gm convert in.bmp -operator gray threshold "50%" out.bmp

   -ordered-dither <channeltype> <NxN>
          ordered dither the image

          The  channel  or  channels specified in the channeltype argument
          are reduced to binary,  using  an  ordered  dither  method.  The
          choices  for  channeltype  are All, Intensity, Red, Green, Blue,
          Cyan, Magenta, Yellow, Black, and Opacity

          When channeltype is "All", the color samples are dithered into a
          gray level and then that gray level is stored in the three color
          channels.  Separately, the opacity channel is  dithered  into  a
          bilevel opacity value which is stored in the opacity channel.

          When  channeltype  is  "Intensity",  only  the color samples are
          dithered. When channeltype is "opacity"  or  "matte",  only  the
          opacity  channel is dithered. When a color channel is specified,
          only that channel is dithered.

          The choices for N are 2 through 7. The image is divided into NxN
          pixel  tiles.   In  each  tile, some or all pixels are turned to
          white depending on their intensity.  For each N, (N**2)+1 levels
          of gray can be represented.  For N == 2, 3, or 4, the pixels are
          turned to white in an order  that  maximizes  dispersion  (i.e.,
          reduces  granularity),  while  for  N  ==  5, 6, and 7, they are
          turned to white in an order  that  creates  a  roughly  circular
          black  blob  in  the  middle of each tile.  An attractive "half-
          tone" looking image can be obtained by first rotating the  image
          45  degrees,  performing  a  5x5  ordered-dither operation, then
          rotating it back to the original orientation and cropping to the
          original  image  dimensions.   If  the  original image is gamma-
          encoded, it is adviseable to  convert  it  to  linear  intensity
          first, e.g., with the "-gamma 0.45455" option.

   -output-directory <directory>
          output files to directory

          Use  -output-directory  to  specify  a  directory under which to
          write the output files. Normally mogrify  overwrites  the  input
          files  but with this option the output files may be written to a
          different directory so that the input files are  preserved.  The
          algorithm  used preserves all of the input path specification in
          the output path so that the user-specified input path (including
          any directory part) is appended to the output path.  The user is
          responsible for creating the output directory.

   -orient <orientation>
          Set the image orientation attribute

          Sets the image orientation  attribute.   The  image  orientation
          attribute  is  compatible with the TIFF orientation tag (and the
          EXIF orientation tag).  Accepted values are undefined,  TopLeft,
          TopRight,    BottomRight,    BottomLeft,    LeftTop,   RightTop,
          RightBottom, LeftBottom, and hyphenated versions  thereof  (e.g.
          left-bottom).   Please note that GraphicsMagick does not include
          an EXIF editor so if an EXIF profile is written  to  the  output
          image,  the value in the EXIF profile might not match the image.
          It is possible for an image file to indicate its orientation  in
          several different ways simultaneously.

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

          Use this option to specify the dimensions of the PostScript page
          in dots per inch or a TEXT page in pixels.  The  choices  for  a
          PostScript page are:

               11x17         792  1224
               Ledger       1224   792
               Legal         612  1008
               Letter        612   792
               LetterSmall   612   792
               ArchE        2592  3456
               ArchD        1728  2592
               ArchC        1296  1728
               ArchB         864  1296
               ArchA         648   864
               A0           2380  3368
               A1           1684  2380
               A2           1190  1684
               A3            842  1190
               A4            595   842
               A4Small       595   842
               A5            421   595
               A6            297   421
               A7            210   297
               A8            148   210
               A9            105   148
               A10            74   105
               B0           2836  4008
               B1           2004  2836
               B2           1418  2004
               B3           1002  1418
               B4            709  1002
               B5            501   709
               C0           2600  3677
               C1           1837  2600
               C2           1298  1837
               C3            918  1298
               C4            649   918
               C5            459   649
               C6            323   459
               Flsa          612   936
               Flse          612   936
               HalfLetter    396   612

          For convenience you can specify the page size by media (e.g. A4,
          Ledger, etc.). Otherwise,  -page  behaves  much  like  -geometry
          (e.g.  -page letter+43+43>).

          This  option  is  also used to place subimages when writing to a
          multi-image format that supports offsets, such as GIF89 and MNG.
          When used for this purpose the offsets are always  measured from
          the top left corner of the canvas and are not  affected  by  the
          -gravity   option.    To  position  a  GIF  or  MNG  image,  use
          -page{+-}<x>{+-}<y> (e.g. -page +100+200).  When  writing  to  a
          MNG  file,  a -page option appearing ahead of the first image in
          the sequence with nonzero width and height defines the width and
          height  values  that  are written in the MHDR chunk.  Otherwise,
          the MNG width and height are computed from the bounding box that
          contains all images in the sequence.  When writing a GIF89 file,
          only  the  bounding  box  method  is  used  to   determine   its
          dimensions.

          For  a  PostScript  page, the image is sized as in -geometry and
          positioned relative to the lower left hand corner of the page by
          {+-}<xoffset>{+-}<y offset>. Use -page 612x792>, for example, to
          center the image within the page. If the image size exceeds  the
          PostScript  page,  it  is  reduced to fit the page.  The default
          gravity for the -page option is NorthWest, i.e., positive x  and
          y  offset  are measured rightward and downward from the top left
          corner of the page, unless the -gravity option is present with a
          value other than NorthWest.

          The default page dimensions for a TEXT image is 612x792.

          This option is used in concert with -density.

          Use +page to remove the page settings for an image.

   -paint <radius>
          simulate an oil painting

          Each  pixel is replaced by the most frequent color in a circular
          neighborhood whose width is specified with radius.

   -pause <seconds>
          pause between animation loops [animate]

          Pause for the specified number of seconds before  repeating  the
          animation.

   -pause <seconds>
          pause between snapshots [import]

          Pause for the specified number of seconds before taking the next
          snapshot.

   -pen <color>
          (This option has been replaced by the -fill option)

   -ping  efficiently determine image characteristics

          Use this option to disable reading  the  image  pixels  so  that
          image  characteristics  such  as  the  image  dimensions  may be
          obtained very quickly. For identify, use +ping to force  reading
          the  image pixels so that the pixel read rate may be included in
          the displayed information.

   -pointsize <value>
          pointsize of the PostScript, X11, or TrueType font

   -preview <type>
          image preview type

          Use this option to affect the  preview  operation  of  an  image
          (e.g.    convert  file.png  -preview  Gamma  Preview:gamma.png).
          Choose from these previews:

               Rotate
               Shear
               Roll
               Hue
               Saturation
               Brightness
               Gamma
               Spiff
               Dull
               Grayscale
               Quantize
               Despeckle
               ReduceNoise
               AddNoise
               Sharpen
               Blur
               Threshold
               EdgeDetect
               Spread
               Shade
               Raise
               Segment
               Solarize
               Swirl
               Implode
               Wave
               OilPaint
               CharcoalDrawing
               JPEG

          The default preview is JPEG.

   -process <command>
          process a sequence of images using a process module

          The command argument has the form module=arg1,arg2,arg3,...,argN
          where  module  is  the  name  of  the  module  to  invoke  (e.g.
          "analyze") and arg1,arg2,arg3,...,argN are an  arbitrary  number
          of  arguments  to  pass  to the process module.  The sequence of
          images is terminated by the appearance of any option.

          If the -process option appears after all of  the  input  images,
          all images are processed.

   -profile <filename>
          add ICM, IPTC, or generic profile  to image

          -profile  filename  adds  an  ICM  (ICC  color management), IPTC
          (newswire information), or a generic (including Exif) profile to
          the image

          Use  +profile  icm,  +profile  iptc, or +profile profile_name to
          remove the respective profile.  Multiple profiles may be listed,
          separated  by  commas.  Profiles may be excluded from subsequent
          listed matches by  preceding  their  name  with  an  exclamation
          point.   For  example,  +profile  '!icm,*'  strips  all profiles
          except for the ICM profile.  Use identify -verbose to  find  out
          what profiles are in the image file.  Use +profile "*" to remove
          all profiles.  Writing the image  to  a  format  that  does  not
          support  profiles  will  of course also cause all profiles to be
          removed.  The JPEG and PNG formats will store any profiles  that
          have been read and not removed.  In JPEG they are stored in APP1
          markers, and in PNG they  are  stored  as  hex-coded  binary  in
          compressed zTXt chunks, except for the iCC chunk which is stored
          in the iCCP chunk.

          To extract a profile, the -profile option is not used.  Instead,
          simply  write  the  file  to an image format such as APP1, 8BIM,
          ICM, or IPTC.

          For example, to extract the Exif data (which is stored  in  JPEG
          files in the APP1 profile), use

              gm convert cockatoo.jpg exifdata.app1

          Note  that GraphicsMagick does not attempt to update any profile
          to reflect changes  made  to  the  image,  e.g.,  rotation  from
          portrait  to  landscape  orientation, so it is possible that the
          preserved profile may contain invalid data.

   -preserve-timestamp
          preserve the original timestamps of the file

          Use this option to preserve the original modification and access
          timestamps of the file, even if it has been modified.

   +progress
          disable progress monitor and busy cursor

          By  default,  when an image is displayed, a progress monitor bar
          is shown in the top left corner of  an  existing  image  display
          window,  and  the  current  cursor is replaced with an hourglass
          cursor. Use +progress to disable the progress monitor  and  busy
          cursor during display operations.  While the progress monitor is
          disabled for all operations, the busy  cursor  continues  to  be
          enabled  for  non-display  operations  such as image processing.
          This option is useful for non-interactive display operations, or
          when a "clean" look is desired.

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level
           For the JPEG and MPEG image formats, quality is 0 (lowest image
          quality and highest compression) to 100 (best quality but  least
          effective  compression).  The  default  quality  is 75.  Use the
          -sampling-factor  option  to  specify  the  factors  for  chroma
          downsampling.   To  use  the same quality value as that found by
          the JPEG decoder, use the -define jpeg:preserve-settings flag.

          For the MIFF image format, and the TIFF format while  using  ZIP
          compression,  quality/10 is the zlib compression level, which is
          0 (worst but fastest compression) to 9 (best  but  slowest).  It
          has  no effect on the image appearance, since the compression is
          always lossless.

          For the JPEG-2000 image format, quality is mapped using  a  non-
          linear  equation to the compression ratio required by the Jasper
          library.  This  non-linear  equation  is  intended  to   loosely
          approximate  the  quality  provided  by  the JPEG v1 format. The
          default  quality  value  75  results  in  a  request  for   16:1
          compression. The quality value 100 results in a request for non-
          lossy compression.

          For the MNG and PNG image formats, the quality  value  sets  the
          zlib compression level (quality / 10) and filter-type (quality %
          10). Compression levels range from 0  (fastest  compression)  to
          100  (best  but  slowest). For compression level 0, the Huffman-
          only strategy is used, which is fastest but not necessarily  the
          worst compression.

          If  filter-type  is 4 or less, the specified filter-type is used
          for all scanlines:

               0: none
               1: sub
               2: up
               3: average
               4: Paeth

          If filter-type is 5, adaptive filtering is used when quality  is
          greater  than  50  and  the  image  does  not  have a color map,
          otherwise no filtering is used.

          If filter-type is 6,  adaptive  filtering  with  minimum-sum-of-
          absolute-values is used.

          Only  if  the output is MNG, if filter-type is 7, the LOCO color
          transformation  and  adaptive  filtering  with   minimum-sum-of-
          absolute-values are used.

          The  default  is  quality  is  75,  which  means nearly the best
          compression with adaptive filtering.  The quality setting has no
          effect  on  the  appearance  of  PNG  and  MNG images, since the
          compression is always lossless.

          For further information, see the PNG specification.

          When writing a JNG image with transparency, two  quality  values
          are  required,  one for the main image and one for the grayscale
          image that conveys the opacity channel.  These are written as  a
          single  integer  equal to the main image quality plus 1000 times
          the opacity quality.  For example, if you want to use quality 75
          for  the main image and quality 90 to compress the opacity data,
          use -quality 90075.

          For the PNM family of formats (PNM,  PGM,  and  PPM)  specify  a
          quality  factor  of zero in order to obtain the ASCII variant of
          the format. Note that -compress none used to be used to  trigger
          ASCII  output  but  provided  the  opposite  result  of what was
          expected as compared with other formats.

   -raise <width>x<height>
          lighten or darken image edges

          This will create a 3-D effect. See -geometry for details details
          about the geometry specification. Offsets are not used.

          Use -raise to create a raised effect, otherwise use +raise.

   -random-threshold <channeltype> <LOWxHIGH>
          random threshold the image

          The  channel or channels specified in the <channeltype> argument
          are reduced to binary, using  an  random-threshold  method.  The
          choices  for  channeltype  are All, Intensity, Red, Green, Blue,
          Cyan, Magenta, Yellow, Black, and Opacity

          When channeltype is "All", the  color  samples  are  thresholded
          into a graylevel and then that gray level is stored in the three
          color channels. Separately, the opacity channel  is  thresholded
          into  a  bilevel  opacity  value  which is stored in the opacity
          channel. For  each  pixel,  a  new  random  number  is  used  to
          establish  the threshold to be used. The threshold never exceeds
          the  specified  maximum  (HIGH)  and  is  never  less  than  the
          specified minimum (LOW).

          When  channeltype  is  "intensity",  only  the color samples are
          thresholded. When channeltype is "opacity" or "matte", only  the
          opacity  channel  is  thresholded. The other named channels only
          threshold the associated channel.

   -recolor <matrix>
          apply a color translation matrix to image channels

          A user supplied color translation matrix (expressed  as  a  text
          string)  is  used to translate/blend the image channels based on
          weightings in a supplied matrix which may be of order  3  (color
          channels  only),  4  (color  channels plus opacity), or 5 (color
          channels plus opacity and offset).  Values in the columns of the
          matrix  (red, green, blue, opacity) are used as multipliers with
          the existing channel values and added together according to  the
          rows of the matrix.  Matrix values are floating point and may be
          negative.  The offset column (column 5) is purely  additive  and
          is  scaled  such  that 0.0 to 1.0 represents the maximum quantum
          range (but values are not limited to this range). The  math  for
          the  color  translation  matrix is similar to that used by Adobe
          Flash except that the offset is  scaled  to  1.0  (divide  Flash
          offset  by  255 for use with GraphicsMagick) so that the results
          are independent of quantum depth.

          An identity matrix exists for each matrix order which results in
          no  change to the image.  The translation matrix should be based
          on an alteration of the identity matrix.

          Identity matrix of order 3

            1 0 0
            0 1 0
            0 0 1

          which may be formatted into a convenient matrix argument similar
          to (comma is treated as white space):

            -recolor "1 0 0, 0 1 0, 0 0 1"

          Identity matrix of order 4

            1 0 0 0
            0 1 0 0
            0 0 1 0
            0 0 0 1

          Identity  matrix  of order 5.  The last row is required to exist
          for the purpose of parsing, but is otherwise not used.

            1 0 0 0 0
            0 1 0 0 0
            0 0 1 0 0
            0 0 0 1 0
            0 0 0 0 1

          As an example, an image wrongly in  BGR  channel  order  may  be
          converted to RGB using this matrix (blue->red, red->blue):

            0 0 1
            0 1 0
            1 0 0

          and  an  RGB  image  using  standard  Rec.709  primaries  may be
          converted to grayscale using this matrix of  standard  weighting
          factors:

            0.2126 0.7152 0.0722
            0.2126 0.7152 0.0722
            0.2126 0.7152 0.0722

          and  contrast may be reduced by scaling down by 80% and adding a
          10% offset:

            0.8 0.0 0.0 0.0 0.1
            0.0 0.8 0.0 0.0 0.1
            0.0 0.0 0.8 0.0 0.1
            0.0 0.0 0.0 0.8 0.1
            0.0 0.0 0.0 0.0 1.0

   -red-primary <x>,<y>
          red chromaticity primary point

   -region <width>x<height>{+-}<x>{+-}<y>
          apply options to a portion of the image

          The x and y offsets are treated in the same manner as in -crop.

   -remote
          perform a X11 remote operation

          The -remote command sends a command to a  "gm  display"  or  "gm
          animate"  which  is already running. The only command recognized
          at this time is  the  name  of  an  image  file  to  load.  This
          capability  is very useful to load new images without needing to
          restart  GraphicsMagick  (e.g.  for  a  slide-show  or  to   use
          GraphicsMagick  as the display engine for a different GUI). Also
          see  the  +progress  option  for  a  way  to  disable   progress
          indication for a clean look while loading new images.

   -render
          render vector operations

          Use  +render  to  turn  off rendering vector operations. This is
          useful when saving the result to vector formats such as  MVG  or
          SVG.

   -repage  <width>x<height>+xoff+yoff[!]
          Adjust image page offsets

          Adjust  the  current  image  page canvas and position based on a
          relative page specification.  This option may be used to  change
          the  location of a subframe (e.g. part of an animation) prior to
          composition.   If  the  geometry   specification   is   absolute
          (includes  a  '!'),  then  the offset adjustment is absolute and
          there is no adjustment to page width and height,  otherwise  the
          page  width  and  height  values  are also adjusted based on the
          current image dimensions.  Use +repage to  set  the  image  page
          offsets to default.

   -resample <horizontal>x<vertical>
          Resample image to specified horizontal and vertical resolution

          Resize  the  image so that its rendered size remains the same as
          the original at the  specified  target  resolution.  Either  the
          current image resolution units or the previously set with -units
          are used to interpret the argument. For example, if  a  300  DPI
          image  renders at 3 inches by 2 inches on a 300 DPI device, when
          the image has been resampled to 72 DPI,  it  will  render  at  3
          inches  by  2 inches on a 72 DPI device.  Note that only a small
          number of image formats (e.g. JPEG, PNG, and TIFF)  are  capable
          of  storing  the  image  resolution.  For  formats  which do not
          support an image resolution,  the  original  resolution  of  the
          image  must  be specified via -density on the command line prior
          to specifying the resample resolution.

          Note that Photoshop stores and obtains image resolution  from  a
          proprietary  embedded  profile.  If  this  profile exists in the
          image, then Photoshop will continue to treat the image using its
          former  resolution,  ignoring  the image resolution specified in
          the standard file header.

          Some image formats (e.g. PNG) require use of metric  or  english
          units  so  even  if  the  original  image used a particular unit
          system,  if  it  is  saved  to  a  different  format  prior   to
          resampling,  then  it  may  be  necessary to specify the desired
          resolution units using -units since the original units may  have
          been  lost.  In  other  words, do not assume that the resolution
          units are restored if the image has been saved to a file.

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

          This is an alias for the -geometry option and it behaves in  the
          same  manner. If the -filter option precedes the -resize option,
          the specified filter is used.

          There are some exceptions:

          When used as a composite option, -resize conveys  the  preferred
          size  of  the output image, while -geometry conveys the size and
          placement of the composite image within the main image.

          When used as a montage option,  -resize  conveys  the  preferred
          size  of  the montage, while -geometry conveys information about
          the tiles.

   -roll {+-}<x>{+-}<y>
          roll an image vertically or horizontally

          See -geometry for details the geometry specification.  The x and
          y offsets are not affected by the -gravity option.

          A  negative x offset rolls the image left-to-right. A negative y
          offset rolls the image top-to-bottom.

   -rotate <degrees>{<}{>}
          rotate the image

          Positive angles rotate the image in a clockwise direction  while
          negative angles rotate counter-clockwise.

          Use  > to rotate the image only if its width exceeds the height.
          < rotates the image only if its width is less than  the  height.
          For example, if you specify -rotate "-90>" and the image size is
          480x640, the image is not rotated.  However,  if  the  image  is
          640x480,  it  is  rotated  by  -90  degrees.  If you use > or <,
          enclose  it  in  quotation  marks  to  prevent  it  from   being
          misinterpreted as a file redirection.

          Empty  triangles  left  over  from rotating the image are filled
          with the color defined as  background  (class  backgroundColor).
          The  color  is  specified  using  the format described under the
          -fill option.

   -sample <geometry>
          scale image using pixel sampling

          See -geometry for  details  about  the  geometry  specification.
          -sample  ignores  the -filter selection if the -filter option is
          present.  Offsets,  if  present  in  the  geometry  string,  are
          ignored, and the -gravity option has no effect.

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

          This  option  specifies  the  sampling factors to be used by the
          DPX, JPEG, MPEG, or YUV encoders for  chroma  downsampling.  The
          sampling  factor  must  be  specified  while reading the raw YUV
          format since it is not preserved in the file header.   Industry-
          standard  video subsampling notation such as "4:2:2" may also be
          used to specify the sampling factors. "4:2:2" is equivalent to a
          specification of "2x1"

          The  JPEG  decoder  obtains  the  original sampling factors (and
          quality settings) when a  JPEG  file  is  read.  To  re-use  the
          original  sampling  factors  (and  quality setting) when JPEG is
          output, use the -define jpeg:preserve-settings flag.

   -scale <geometry>
          scale the image.

          See -geometry for  details  about  the  geometry  specification.
          -scale  uses  a  simpler,  faster  algorithm, and it ignores the
          -filter selection if the -filter option is present.  Offsets, if
          present  in  the  geometry string, are ignored, and the -gravity
          option has no effect.

   -scene <value>
          set scene number

          This option sets the scene number of an image or the first image
          in an image sequence.

   -scenes <value-value>
          range of image scene numbers to read

          Each  image in the range is read with the filename followed by a
          period (.) and the decimal scene number.  You  can  change  this
          behavior  by  embedding a %d, %0Nd, %o, %0No, %x, or %0Nx printf
          format specification in the file name. For example,

              gm montage -scenes 5-7 image.miff montage.miff

          makes  a  montage  of  files  image.miff.5,  image.miff.6,   and
          image.miff.7, and

              gm animate -scenes 0-12 image%02d.miff

          animates files image00.miff, image01.miff, through image12.miff.

   -screen
          specify the screen to capture

          This  option  indicates that the GetImage request used to obtain
          the image should  be  done  on  the  root  window,  rather  than
          directly  on  the specified window.  In this way, you can obtain
          pieces of other windows that overlap the specified  window,  and
          more importantly, you can capture menus or other popups that are
          independent windows but appear over the specified window.

   -set <attribute> <value>
          set an image attribute

          Set a named image  attribute.   The  attribute  is  set  on  the
          current (previously specified on command line) image.

   +set <attribute>
          unset an image attribute

          Unset  a  named  image attribute.  The attribute is removed from
          the current (previously specified on command line) image.

   -segment <cluster threshold>x<smoothing threshold>
          segment an image

          Segment an image  by  analyzing  the  histograms  of  the  color
          components  and  identifying units that are homogeneous with the
          fuzzy c-means technique.

          Segmentation is a very useful fast  and  and  approximate  color
          quantization  algorithm  for  scanned  printed  pages or scanned
          cartoons. It may also be  used  as  a  special  effect.  Specify
          cluster threshold as the minimum percentage of total pixels in a
          cluster  before  it  is  considered  valid.   For  huge   images
          containing  small detail, this may need to be a tiny fraction of
          a percent (e.g. 0.015) so that important  detail  is  not  lost.
          Smoothing threshold eliminates noise in the second derivative of
          the histogram. As the value  is  increased,  you  can  expect  a
          smoother second derivative. The default is 1.5. Add the -verbose
          option to see a dump of cluster statistics given the  parameters
          used.  The  statistics  may be used as a guide to help fine tune
          the options.

   -shade <azimuth>x<elevation>
          shade the image using a distant light source

          Specify azimuth and elevation  as  the  position  of  the  light
          source.  Use +shade to return the shading results as a grayscale
          image.

   -shadow <radius>{x<sigma>}
          shadow the montage

   -shared-memory
          use shared memory

          This option specifies whether the utility should attempt to  use
          shared memory for pixmaps.  GraphicsMagick must be compiled with
          shared memory support, and the display must support the  MIT-SHM
          extension.   Otherwise,  this option is ignored.  The default is
          True.

   -sharpen <radius>{x<sigma>}
          sharpen the image

          Use a  Gaussian  operator  of  the  given  radius  and  standard
          deviation (sigma).

   -shave <width>x<height>{%}
          shave pixels from the image edges

          Specify the width of the region to be removed from both sides of
          the image and the height of the regions to be removed  from  top
          and bottom.

   -shear <x degrees>x<y degrees>
          shear the image along the X or Y axis

          Use the specified positive or negative shear angle.

          Shearing  slides  one  edge  of  an image along the X or Y axis,
          creating a parallelogram. An X direction shear  slides  an  edge
          along the X axis, while a Y direction shear slides an edge along
          the Y axis. The amount of the shear is  controlled  by  a  shear
          angle. For X direction shears, x degrees is measured relative to
          the Y axis, and similarly, for Y direction shears y  degrees  is
          measured relative to the X axis.

          Empty  triangles  left  over  from shearing the image are filled
          with the color defined as  background  (class  backgroundColor).
          The  color  is  specified  using  the format described under the
          -fill option.

   -silent
          operate silently

   -size <width>x<height>{+offset}
          width and height of the image

          Use this option to specify the width and height  of  raw  images
          whose  dimensions  are  unknown  such  as GRAY, RGB, or CMYK. In
          addition to width and height, use -size with an offset  to  skip
          any header information in the image or tell the number of colors
          in a MAP image file, (e.g. -size 640x512+256).

          For Photo CD images, choose from these sizes:

               192x128
               384x256
               768x512
               1536x1024
               3072x2048

          Finally, use this option to choose a particular resolution layer
          of a JBIG or JPEG image (e.g. -size 1024x768).

   -snaps <value>
          number of screen snapshots

          Use  this  option  to grab more than one image from the X server
          screen, to create an animation sequence.

   -solarize <factor>
          negate all pixels above the threshold level

          Specify factor as the percent threshold of the  intensity  (0  -
          99.9%).

          This  option produces a solarization effect seen when exposing a
          photographic film to light during the development process.

   -spread <amount>
          displace image pixels by a random amount

          Amount defines the size of the neighborhood around each pixel to
          choose a candidate pixel to swap.

   -stegano <offset>
          hide watermark within an image

          Use  an  offset  to start the image hiding some number of pixels
          from the beginning of the image.  Note this offset and the image
          size.    You   will   need   this  information  to  recover  the
          steganographic   image   (e.g.    display    -size    320x256+35
          stegano:image.png).

   -stereo
          composite two images to create a stereo anaglyph

          The  left side of the stereo pair is saved as the red channel of
          the output image.  The right side is saved as the green channel.
          Red-green  stereo  glasses  are  required  to  properly view the
          stereo image.

   -strip remove all profiles and text attributes from the image

          All embedded profiles and text attributes are stripped from  the
          image.   This  is  useful  for  images used for the web, or when
          output files need to be as small as possible

   -stroke <color>
          color to use when stroking a graphic primitive

          The color is specified using  the  format  described  under  the
          -fill option.

          See -draw for further details.

   -strokewidth <value>
          set the stroke width

          See -draw for further details.

   -swirl <degrees>
          swirl image pixels about the center

          Degrees defines the tightness of the swirl.

   -text-font <name>
          font for writing fixed-width text

          Specifies  the  name  of  the  preferred  font  to  use in fixed
          (typewriter style) formatted text.   The  default  is  14  point
          Courier.

          You  can  tag  a  font  to  specify  whether it is a PostScript,
          TrueType, or X11 font.  For example, Courier.ttf is  a  TrueType
          font and x:fixed is X11.

   -texture <filename>
          name of texture to tile onto the image background

   -threshold <value>{%}
          threshold the image

          Modify  the  image  such that any pixel sample with an intensity
          value  greater  than  the  threshold  is  assigned  the  maximum
          intensity   (white),   or  otherwise  is  assigned  the  minimum
          intensity (black). If a percent  prefix  is  applied,  then  the
          threshold is a percentage of the available range.

          To  efficiently  create  a  black  and  white image from a color
          image, use

              gm convert -threshold 50% in.png out.png

          The optimum threshold value depends on the nature of the  image.
          In  order  to  threshold  individual channels, use the -operator
          subcommand with it's Threshold, Threshold-White,  or  Threshold-
          Black options.

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

          The -thumbnail command resizes the image as quickly as possible,
          with more  concern  for  speed  than  resulting  image  quality.
          Regardless,  resulting  image  quality  should be acceptable for
          many uses.  It is primarily intended  to  be  used  to  generate
          smaller  versions  of the image, but may also be used to enlarge
          the image.  The -thumbnail geometry argument observes  the  same
          syntax and rules as it does for -resize.

   -tile <filename>
          tile image when filling a graphic primitive

   -tile <geometry>
          layout of images [montage]

   -title <string>
          assign title to displayed image [animate, display, montage]

          Use this option to assign a specific title to the image. This is
          assigned to the image window and is typically displayed  in  the
          window   title  bar.   Optionally  you  can  include  the  image
          filename,  type,  width,  height,  Exif  data,  or  other  image
          attribute by embedding special format characters described under
          the -format option.

          For example,

               -title "%m:%f %wx%h"

          produces an image title of MIFF:bird.miff 512x480 for  an  image
          titled bird.miff and whose width is 512 and height is 480.

   -transform
          transform the image

          This  option  applies  the transformation matrix from a previous
          -affine option.

              gm convert -affine 2,2,-2,2,0,0 -transform bird.ppm bird.jpg

   -transparent <color>
          make this color transparent within the image

          The color is specified using  the  format  described  under  the
          -fill option.

   -treedepth <value>
          tree depth for the color reduction algorithm

          Normally,  this integer value is zero or one. A value of zero or
          one causes the use of  an  optimal  tree  depth  for  the  color
          reduction algorithm

          An optimal depth generally allows the best representation of the
          source image with the fastest computational speed and the  least
          amount  of  memory.  However, the default depth is inappropriate
          for some images. To assure the best representation,  try  values
          between  2 and 8 for this parameter.  Refer to quantize for more
          details.

          The -colors or -monochrome option, or writing to an image format
          which  requires  color reduction, is required for this option to
          take effect.

   -trim  trim an image

          This option removes any edges that are exactly the same color as
          the  corner  pixels.   Use -fuzz to make -trim remove edges that
          are nearly the same color as the corner pixels.

   -type <type>
          the image type

          Choose  from:   Bilevel,   Grayscale,   Palette,   PaletteMatte,
          TrueColor,            TrueColorMatte,           ColorSeparation,
          ColorSeparationMatte, or Optimize.

          Normally, when a format supports different  subformats  such  as
          bilevel, grayscale, palette, truecolor, and truecolor+alpha, the
          encoder will try to choose a suitable  subformat  based  on  the
          nature  of the image. The -type option may be used to tailor the
          output subformat. By default the output subformat  is  based  on
          readily  available  image  information and is usually similar to
          the input format.

          Specify -type Optimize in order to enable inspecting all  pixels
          (if  necessary)  in  order to find the most efficient subformat.
          Inspecting all of the pixels may be slow for very large  images,
          particularly if they are stored in a disk cache. If an RGB image
          contains only gray pixels, then every pixel in the image must be
          inspected  in  order  to  decide  that  the  image  is  actually
          grayscale!

          Sometimes a specific subformat is desired. For example, to force
          a  JPEG  image to be written in TrueColor RGB format even though
          only gray pixels are present, use

              gm convert bird.pgm -type TrueColor bird.jpg

          Similarly, using -type TrueColorMatte will force the encoder  to
          write  an  alpha channel even though the image is opaque, if the
          output format supports transparency.

          Some pseudo-formats  (e.g.  the  XC  format)  will  respect  the
          requested type if it occurs previously on the command line.  For
          example, to obtain a DirectClass solid color canvas image rather
          than PsuedoClass, use

              gm convert -size 640x480 -type TrueColor xc:red red.miff

          Likewise,   specify  -type  Bilevel,  Grayscale,  TrueColor,  or
          TrueColorMatte prior to reading a Postscript (or  PDF  file)  in
          order  to  influence  the type of image that Ghostcript returns.
          Reading  performance   will   be   dramatically   improved   for
          black/white  Postscript  if  Bilevel  is  specified, and will be
          considerably faster if Grayscale is specified.

   -update <seconds>
           detect when image file is modified and redisplay.

          Suppose that while you are displaying an image the file that  is
          currently displayed is over-written.  display will automatically
          detect that the input file  has  been  changed  and  update  the
          displayed image accordingly.

   -units <type>
          the units of image resolution

          Choose  from:  Undefined, PixelsPerInch, or PixelsPerCentimeter.
          This option is normally used in conjunction  with  the  -density
          option.

   -unsharp <radius>{x<sigma>}{+<amount>}{+<threshold>}
          sharpen the image with an unsharp mask operator

          The  -unsharp  option  sharpens an image. The image is convolved
          with a Gaussian  operator  of  the  given  radius  and  standard
          deviation  (sigma).  For  reasonable  results,  radius should be
          larger than sigma. Use a radius of 0 to have the method select a
          suitable radius.

          The parameters are:

           radius

                The  radius  of  the Gaussian, in pixels, not counting the
                center pixel (default 0).

           sigma

                The standard deviation of the Gaussian, in pixels (default
                1.0).

           amount

                The  percentage of the difference between the original and
                the blur image  that  is  added  back  into  the  original
                (default 1.0).

           threshold

                The  threshold,  as  a fraction of MaxRGB, needed to apply
                the difference amount (default 0.05).

   -use-pixmap
          use the pixmap

   -verbose
          print detailed information about the image

          This information is printed: image  scene  number;  image  name;
          image  size;  the  image class (DirectClass or PseudoClass); the
          total number of unique colors; and the number of seconds to read
          and  transform the image. If the image is DirectClass, the total
          number of unique colors is  not  displayed  unless  -verbose  is
          specified  twice since it may take quite a long time to compute,
          particularly for deep images.  If the image is PseudoClass  then
          its  pixels are defined by indexes into a colormap. If the image
          is  DirectClass  then  each  pixel  includes  a   complete   and
          independent color specification.

          If  -colors  is  also  specified, the total unique colors in the
          image and color reduction error values  are  printed.  Refer  to
          quantize for a description of these values.

   -version
          print GraphicsMagick version string

   -view <string>
          FlashPix viewing parameters

   -virtual-pixel <method>
          specify contents of "virtual pixels"

          This  option defines "virtual pixels" for use in operations that
          can access pixels outside the boundaries of an image.

          Choose from these methods:

           Constant

                Use the image background color.

           Edge

                Extend the edge pixel toward infinity (default).

           Mirror

                Mirror the image.

           Tile

                Tile the image.

           This option affects operations that use virtual pixels such  as
           -blur, -sharpen, -wave, etc.

   -visual <type>
          animate images using this X visual type

          Choose from these visual classes:

               StaticGray
               GrayScale
               StaticColor
               PseudoColor
               TrueColor
               DirectColor
               default
               visual id

          The  X  server  must support the visual you choose, otherwise an
          error occurs.  If a visual is not specified,  the  visual  class
          that  can  display  the  most simultaneous colors on the default
          screen is chosen.

   -watermark <brightness>x<saturation>
          percent brightness and saturation of a watermark

   -wave <amplitude>x<wavelength>
          alter an image along a sine wave

          Specify amplitude and wavelength of the wave.

   -white-point <x>,<y>
          chromaticity white point

   -white-threshold red[,green][,blue][,opacity]
          pixels above the threshold become white

          Use  -white-threshold  to  set  pixels  with  values  above  the
          specified  threshold to maximum value (white). If only one value
          is supplied, or the red, green, and blue values  are  identical,
          then  intensity  thresholding  is  used.  If the color threshold
          values are not  identical  then  channel-based  thresholding  is
          used,  and color distortion will occur. Specify a negative value
          (e.g. -1) if you want a channel to be ignored but you do want to
          threshold  a  channel later in the list. If a percent (%) symbol
          is appended, then the values are  treated  as  a  percentage  of
          maximum range.

   -window <id>
          make image the background of a window

          id  can be a window id or name.  Specify root to select X's root
          window as the target window.

          By default the image is tiled onto the background of the  target
          window.    If  backdrop or -geometry are specified, the image is
          surrounded by the background color.  Refer to  X  RESOURCES  for
          details.

          The  image  will not display on the root window if the image has
          more unique colors than the target window colormap allows.   Use
          -colors to reduce the number of colors.

   -window-group
          specify the window group

   -write <filename>
          write an intermediate image [convert, composite]

          The  current image is written to the specified filename and then
          processing continues using  that  image.  The  following  is  an
          example of how several sizes of an image may be generated in one
          command (repeat as often as needed):

              gm convert input.jpg -resize 50% -write input50.jpg \
                        -resize 25% input25.jpg

   -write <filename>
          write the image to a file [display]

          If filename already exists, you will be prompted as  to  whether
          it should be overwritten.

          By  default, the image is written in the format that it was read
          in as.  To specify a particular image  format,  prefix  filename
          with  the image type and a colon (e.g., ps:image) or specify the
          image type as the filename suffix (e.g., image.ps). Specify file
          as  -  for standard output. If file has the extension .Z or .gz,
          the file size is compressed using compress or gzip respectively.
          Precede the image file name with | to pipe to a system command.

          Use -compress to specify the type of image compression.

          The  equivalent  X  resource  for  this  option is writeFilename
          (class WriteFilename).  See "X Resources", below, for details.

ENVIRONMENT

   COLUMNS
          Output screen width. Used when formatting text for  the  screen.
          Many  Unix  systems  keep this shell variable up to date, but it
          may need to be explicitly exported in order  for  GraphicsMagick
          to see it.

   DISPLAY
          X11  display  ID  (host,  display number, and screen in the form
          hostname:display.screen).

   HOME   Location of user's home directory. GraphicsMagick  searches  for
          configuration  files  in  $HOME/.magick if the directory exists.
          See   MAGICK_CODER_MODULE_PATH,    MAGICK_CONFIGURE_PATH,    and
          MAGICK_FILTER_MODULE_PATH if more flexibility is needed.

   MAGICK_ACCESS_MONITOR
          When  set  to  TRUE,  command  line  monitor  mode  (enabled  by
          -monitor) will also show  files  accessed  (including  temporary
          files)  and  any  external  commands which are executed. This is
          useful  for  debugging,  but  also  illustrates  arguments  made
          available    to    an   access   handler   registered   by   the
          MagickSetConfirmAccessHandler() C library function.

   MAGICK_CODER_STABILITY
          The minimum coder stability level before it will  be  used.  The
          available levels are PRIMARY, STABLE, UNSTABLE, and BROKEN.  The
          default  minimum  level  is  UNSTABLE,  which  means  that   all
          available  working  coders  will  be  used.  The purpose of this
          option  is  to  reduce  the  security  exposure   (or   apparent
          complexity)  due to the huge number of formats supported. Coders
          at the PRIMARY level are commonly used formats  with  very  well
          maintained  implementations.  Coders  at  the  STABLE  level are
          reasonably well maintained  but  represent  less  used  formats.
          Coders  at  the UNSTABLE level either have weak implementations,
          the file format itself is weak, or  the  probability  the  coder
          will  be needed is vanishingly small. Coders at the BROKEN level
          are known to often not work properly or might not be  useful  in
          their current state at all.

   MAGICK_CODER_MODULE_PATH
          Search  path  to  use  when  searching  for  image  format coder
          modules.  This path allows the user to  arbitrarily  extend  the
          image  formats  supported  by  GraphicsMagick by adding loadable
          modules to an arbitrary location rather than copying  them  into
          the GraphicsMagick installation directory. The formatting of the
          search path is similar to operating system  search  paths  (i.e.
          colon delimited for Unix, and semi-colon delimited for Microsoft
          Windows). This user specified search path is used before  trying
          the default search path.

   MAGICK_CONFIGURE_PATH
          Search  path  to  use  when  searching  for configuration (.mgk)
          files.   The  formatting  of  the  search  path  is  similar  to
          operating  system  search  paths (i.e. colon delimited for Unix,
          and semi-colon  delimited  for  Microsoft  Windows).  This  user
          specified  search  path is used before trying the default search
          path.

   MAGICK_DEBUG
          Debug options (see -debug for details).  Setting  debug  options
          via  an  environment  variable is currently necessary to see the
          complete initialization process.

   MAGICK_FILTER_MODULE_PATH
          Search path to use when searching  for  filter  process  modules
          (invoked via -process). This path allows the user to arbitrarily
          extend GraphicsMagick's image processing functionality by adding
          loadable  modules  to  an arbitrary location rather than copying
          them  into  the  GraphicsMagick  installation   directory.   The
          formatting  of  the  search  path is similar to operating system
          search paths (i.e. colon  delimited  for  Unix,  and  semi-colon
          delimited  for  Microsoft  Windows).  This user specified search
          path is used before trying the default search path.

   MAGICK_GHOSTSCRIPT_PATH
          For Microsoft Windows,  specify  the  path  to  the  Ghostscript
          installation  rather  than  searching  for  it  via  the Windows
          registry.  This helps in case Ghostscript is not  installed  via
          the Ghostscript Windows installer or the user wants more control
          over the Ghostscript used.

   MAGICK_HOME
          Path to  top  of  GraphicsMagick  installation  directory.  Only
          observed  by "uninstalled" builds of GraphicsMagick which do not
          have their location hard-coded or set by an installer.

   MAGICK_MMAP_READ
          If MAGICK_MMAP_READ is set to TRUE, GraphicsMagick will  attempt
          to   memory-map   the  input  file  for  reading.  This  usually
          substantially improves repeated read performance since the  file
          is  already  in  memory  after  the first time it has been read.
          However, testing shows that performance may be reduced for files
          accessed  for  the  first  time since data is accessed via page-
          faults (upon first access) and many operating systems fail to do
          sequential  read-ahead  of memory mapped files, and particularly
          if those files are accessed over a network.  If many large input
          files  are  read, then enabling this option may harm performance
          by overloading the operating system's VM system as it then needs
          to free unmapped pages and map new ones.

   MAGICK_IO_FSYNC
          If  MAGICK_IO_FSYNC  is  set  to  TRUE, then GraphicsMagick will
          request that the output file is fully flushed  and  synchronized
          to  disk  when  it is closed. This incurs a performance penalty,
          but has the benefit that  if  the  power  fails  or  the  system
          crashes,  the  file  should be valid on disk. If image files are
          referenced from a database, then this option helps  assure  that
          the files referenced by the database are valid.

   MAGICK_IOBUF_SIZE
          The  amount  of I/O buffering (in bytes) to use when reading and
          writing encoded files. The default is 16384, which  is  observed
          to  work  well  for  many  cases.  The  best  value  for a local
          filesystem is usually the the native filesystem block size (e.g.
          4096,  8192,  or  even 131,072 for ZFS) in order to minimize the
          number of physical disk  I/O  operations.   I/O  performance  to
          files  accessed  over  a  network  may  benefit significantly by
          tuning this option. Larger values  are  not  necessarily  better
          (they  may  be  slower!),  and  there is rarely any benefit from
          using values larger than 32768. Use convert's -verbose option in
          order  to  evaluate  read  and  write rates in pixels per second
          while keeping in mind that the  operating  system  will  try  to
          cache files in RAM.

   MAGICK_LIMIT_DISK
          Maximum amount of disk space allowed for use by the pixel cache.

   MAGICK_LIMIT_FILES
          Maximum number of open files.

   MAGICK_LIMIT_MAP
          Maximum  size  of  a  memory  mapped  file allocation.  A memory
          mapped file consumes memory when the file is accessed,  although
          the system may reclaim such memory when needed.

   MAGICK_LIMIT_MEMORY
          Maximum amount of memory to allocate from the heap.

   MAGICK_LIMIT_PIXELS
          Maximum  number  of total pixels (image rows times image colums)
          to allow for any image which is requested to be created or read.
          This  is  useful  to place a limit on how large an image may be.
          If the input image file has image  dimensions  larger  than  the
          pixel  limit,  then the image memory allocation is denied and an
          error is returned immediately.  This is a  per-image  limit  and
          does  not limit the total number of pixels due to multiple image
          frames/pages (e.g. multi-page document or an animation).

   MAGICK_LIMIT_WIDTH
          Maximum pixel width of an image read, or created.

   MAGICK_LIMIT_HEIGHT
          Maximum pixel height of an image read, or created.

   MAGICK_TMPDIR
          Path to directory where GraphicsMagick  should  write  temporary
          files. The default is to use the system default, or the location
          set by TMPDIR.

   TMPDIR For POSIX-compatible systems (Unix-compatible), the path to  the
          directory  where  all applications should write temporary files.
          Overridden by MAGICK_TMPDIR if it is set.

   TMP or TEMP
          For  Microsoft  Windows,  the  path  to  the   directory   where
          applications   should   write  temporary  files.  Overridden  by
          MAGICK_TMPDIR if it is set.

   OMP_NUM_THREADS
          As per the OpenMP standard, this specifies the number of threads
          to use in parallel regions. Some compilers default the number of
          threads to use to the number of processor cores available  while
          others  default to just one thread. See the OpenMP specification
          for other standard adjustments and your  compiler's  manual  for
          vendor-specific settings.

CONFIGURATION FILES

   GraphicsMagick uses a number of XML format configuration files:

   colors.mgk
          colors configuration file

            <?xml version="1.0"?>
            <colormap>
              <color name="AliceBlue" red="240" green="248" blue="255"
                     compliance="SVG, X11, XPM" />
            </colormap>

   delegates.mgk
          delegates configuration file

   log.mgk
          logging configuration file

            <?xml version="1.0"?>
            <magicklog>
              <log events="None" />
              <log output="stdout" />
              <log filename="Magick-%d.log" />
              <log generations="3" />
              <log limit="2000" />
              <log format="%t %r %u %p %m/%f/%l/%d:\n  %e"  />
            </magicklog>

   modules.mgk
          loadable modules configuration file

            <?xml version="1.0"?>
            <modulemap>
              <module magick="8BIM" name="META" />
            </modulemap>

   type.mgk
          master type (fonts) configuration file

            <?xml version="1.0"?>
            <typemap>
              <include file="type-windows.mgk" />
              <type
                name="AvantGarde-Book"
                fullname="AvantGarde Book"
                family="AvantGarde"
                foundry="URW"
                weight="400"
                style="normal"
                stretch="normal"
                format="type1"
                metrics="/usr/local/share/ghostscript/fonts/a010013l.afm"
                glyphs="/usr/local/share/ghostscript/fonts/a010013l.pfb"
              />
            </typemap>

GM ANIMATE

   Animate  displays  a  sequence  of  images  on  any workstation display
   running an X server. animate first determines the hardware capabilities
   of  the workstation. If the number of unique colors in an image is less
   than or equal to the number the workstation can support, the  image  is
   displayed  in  an X window. Otherwise the number of colors in the image
   is first reduced to match  the  color  resolution  of  the  workstation
   before it is displayed.

   This  means  that a continuous-tone 24 bits-per-pixel image can display
   on a 8 bit pseudo-color device or monochrome device. In most  instances
   the  reduced color image closely resembles the original. Alternatively,
   a  monochrome  or  pseudo-color  image  sequence  can  display   on   a
   continuous-tone 24 bits-per-pixel device.

   To help prevent color flashing on X server visuals that have colormaps,
   animate creates a single colormap from the image sequence. This can  be
   rather  time consuming. You can speed this operation up by reducing the
   colors in the image before you "animate" them.  Use  mogrify  to  color
   reduce  the  images  to  a single colormap. See mogrify(1) for details.
   Alternatively, you can use a Standard Colormap; or a static, direct, or
   true  color  visual.  You can define a Standard Colormap with xstdcmap.
   See xstdcmap(1) for details. This method is recommended for colormapped
   X server because it eliminates the need to compute a global colormap.

EXAMPLES

   To animate a set of images of a cockatoo, use:

       gm animate cockatoo.*

   To  animate a cockatoo image sequence while using the Standard Colormap
   best, use:

       xstdcmap -best
       gm animate -map best cockatoo.*

   To animate an image of a  cockatoo  without  a  border  centered  on  a
   backdrop, use:

       gm animate +borderwidth -backdrop cockatoo.*

OPTIONS

   For a more detailed description of each option, see Options, above.

   -authenticate <string>
          decrypt image with this password

   -backdrop
          display the image centered on a backdrop.

   -background <color>
          the background color

   -bordercolor <color>
          the border color

   -borderwidth <geometry>
          the border width

   -chop <width>x<height>{+-}<x>{+-}<y>{%}
          remove pixels from the interior of an image

   -colormap <type>
          define the colormap type

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -delay <1/100ths of a second>
          display the next image after pausing

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -font <name>
          use this font when annotating the image with text

   -foreground <color>
          define the foreground color

   -gamma <value>
          level of gamma correction

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -help  print usage instructions

   -iconGeometry <geometry>
          specify the icon geometry

   -iconic
          iconic animation

   -interlace <type>
          the type of interlacing scheme

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -log <string>
          Specify format for debug log

   -map <type>
          display image using this type.

   -matte store matte channel if the image has one

   -mattecolor <color>
          specify the color to be used with the -frame option

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -name  name an image

   -noop  NOOP (no option)

   -pause <seconds>
          pause between animation loops [animate]

   -remote
          perform a X11 remote operation

   -rotate <degrees>{<}{>}
          rotate the image

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scenes <value-value>
          range of image scene numbers to read

   -shared-memory
          use shared memory

   -size <width>x<height>{+offset}
          width and height of the image

   -text-font <name>
          font for writing fixed-width text

   -title <string>
          assign title to displayed image [animate, display, montage]

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -visual <type>
          animate images using this X visual type

   -window <id>
          make image the background of a window

          For a more detailed description of  each  option,  see  Options,
          above.

          Any option you specify on the command line remains in effect for
          the group of images following it, until the group is  terminated
          by  the  appearance  of  any  option  or -noop.  For example, to
          animate three images, the first with 32 colors, the second  with
          an  unlimited  number  of  colors,  and  the  third with only 16
          colors, use:

              gm animate -colors 32 cockatoo.1 -noop cockatoo.2
                       -colors 16 cockatoo.3

          Animate options can appear on the command  line  or  in  your  X
          resources  file. See X(1). Options on the command line supersede
          values specified in your X resources file.  Image filenames  may
          appear  in  any order on the command line if the image format is
          MIFF (refer to miff(5) and the scene keyword is specified in the
          image.  Otherwise  the  images  will  display  in the order they
          appear on the command line.

MOUSE BUTTONS

   Press any button to map or unmap  the  Command  widget.  See  the  next
   section for more information about the Command widget.

COMMAND WIDGET

   The Command widget lists a number of sub-menus and commands. They are

       Animate

           Open
           Play
           Step
           Repeat
           Auto Reverse

       Speed

           Faster
           Slower

       Direction

           Forward
           Reverse

       Image Info
       Help
       Quit

   Menu  items  with  a  indented  triangle  have  a  sub-menu.  They  are
   represented above as the indented items. To  access  a  sub-menu  item,
   move  the  pointer to the appropriate menu and press a button and drag.
   When you find the desired sub-menu item, release  the  button  and  the
   command  is  executed.   Move the pointer away from the sub-menu if you
   decide not to execute a particular command.

KEYBOARD ACCELERATORS

           Ctl+O

                Press to load an image from a file.
           space

                Press to display the next image in the sequence.
           <

                Press to speed-up the display of  the  images.   Refer  to
                -delay for more information.
           >

                Press  to slow the display of the images.  Refer to -delay
                for more information.
           ?

                Press to display information about the image.   Press  any
                key or button to erase the information.
                This  information is printed: image name;  image size; and
                the total number of unique colors in the image.
           F1

                Press to display helpful information about animate(1).
           Ctl-q

                Press to discard all images and exit program.

X RESOURCES

   Animate options can appear on the command line or in  your  X  resource
   file.  Options on the command line supersede values specified in your X
   resource file. See X(1) for more information on X resources.

   All animate options have a corresponding X resource. In  addition,  the
   animate program uses the following X resources:

           background (class Background)

                Specifies  the preferred color to use for the Image window
                background. The default is #ccc.
           borderColor (class BorderColor)

                Specifies the preferred color to use for the Image  window
                border. The default is #ccc.
           borderWidth (class BorderWidth)

                Specifies  the width in pixels of the Image window border.
                The default is 2.
           font (class Font or FontList)

                Specifies the name of the preferred font to use in  normal
                formatted text.  The default is 14 point Helvetica.
           foreground (class Foreground)

                Specifies  the  preferred color to use for text within the
                Image window.  The default is black.
           geometry (class geometry)

                Specifies the preferred size and  position  of  the  image
                window.  It  is  not  necessarily  obeyed  by  all  window
                managers.  Offsets, if present, are handled in X(1) style.
                A negative x offset is measured from the right edge of the
                screen to the right edge of the icon,  and  a  negative  y
                offset  is  measured from the bottom edge of the screen to
                the bottom edge of the icon.
           iconGeometry (class IconGeometry)

                Specifies  the  preferred  size  and   position   of   the
                application  when iconified.  It is not necessarily obeyed
                by all window managers.  Offsets, if present, are  handled
                in the same manner as in class Geometry.
           iconic (class Iconic)

                This  resource  indicates  that  you would prefer that the
                application's windows initially not be visible as  if  the
                windows  had  be  immediately  iconified  by  you.  Window
                managers  may  choose  not  to  honor  the   application's
                request.
           matteColor (class MatteColor)

                Specify   the  color  of  windows.  It  is  used  for  the
                backgrounds of windows, menus, and notices. A 3D effect is
                achieved by using highlight and shadow colors derived from
                this color. Default value: #ddd.
           name (class Name)

                This resource specifies the name under which resources for
                the  application  should be found. This resource is useful
                in shell aliases to distinguish between invocations of  an
                application,  without resorting to creating links to alter
                the executable file name. The default is  the  application
                name.
           sharedMemory (class SharedMemory)

                This resource specifies whether animate should attempt use
                shared memory for pixmaps. ImageMagick  must  be  compiled
                with  shared  memory support, and the display must support
                the  MIT-SHM  extension.  Otherwise,  this   resource   is
                ignored. The default is True.
           text_font (class textFont)

                Specifies  the  name of the preferred font to use in fixed
                (typewriter style) formatted text. The default is 14 point
                Courier.
           title (class Title)

                This resource specifies the title to be used for the Image
                window. This information is sometimes  used  by  a  window
                manager  to  provide  some  sort of header identifying the
                window. The default is the image file name.

GM BATCH

DESCRIPTION

   batch executes  an  arbitary  number  of  the  utility  commands  (e.g.
   convert)  in  the  form  of  a  simple  linear batch script in order to
   improve execution efficiency, and/or to allow use as a subordinate  co-
   process under the control of an arbitrary script or program.

EXAMPLES

    To  drive 'gm batch' using a shell script (or a program written in any
   language), have the script/program send commands to 'gm batch' via  its
   standard  input.   Specify  that standard input should be used by using
   '-' as the  file  name.   The  following  example  converts  all  files
   matching  '*.jpg' to TIFF format while rotating each file by 90 degrees
   and stripping all  embedded  profiles.   The  shell  script  syntax  is
   standard Unix shell:

     for file in *.jpg
     do
       outfile=`basename $file .jpg`.tiff
       echo convert -verbose "'$file'" -rotate 90 \
       +profile "'*'" "'$outfile'"
     done | gm batch -echo on -feedback on -

   We  can  accomplish the same as the previous example by putting all the
   commands in a text file and then specifying the name of the  text  file
   as the script to execute:

     for file in *.jpg
     do
       outfile=`basename $file .jpg`.tiff
       echo convert -verbose "'$file'" -rotate 90 \
       +profile "'*'" "'$outfile'"
     done > script.txt
     gm batch -echo on -feedback on script.txt

OPTIONS

   Options  are  processed  from  left to right and must appear before any
   filename argument.

   -echo on|off
          command echo on or off

          Specify on to enable echoing commands to standard output as they
          are read or off to disable.  The default is off.

   -escape unix|windows
          Parse using unix or windows syntax

          Commands must be parsed from the input stream and escaping needs
          to be used to protect spaces or quoting characters in the input.
          Specify  unix  to use unix-style command line parsing or windows
          for Microsoft Windows command shell style parsing.  The  default
          depends  on if the software is compiled for Microsoft Windows or
          for a Unix-type system (including Cygwin on Microsoft  Windows).
          It is recommended to use unix syntax because it is more powerful
          and more portable.

   -fail text
          text to print if a command fails

          When feedback is enabled, this specifies the text to print  when
          the command fails.  The default text is FAIL.

   -feedback on|off
          enable error feedback

          Print  text  (see  -pass  and -fail options) feedback after each
          command to indicate the result, the default is off.

   -help

          Prints batch command help.

   -pass text
          text to print if a command passes

          When feedback is enabled, this specifies the text to print  when
          the command passes.  The default text is PASS.

   -prompt text
          Prompt text to use for command line

          If  no  filename argument was specified, a simple command prompt
          appears  where  you  may  enter  GraphicsMagick  commands.   The
          default  prompt is GM>.  Use this option to change the prompt to
          something else.

   -stop-on-error on|off
          Specify if command processing stops on error

          Normally command processing continues if a command encounters an
          error.   Specify  -stop-on-error  on to cause processing to quit
          immediately on error.

GM BENCHMARK

DESCRIPTION

   benchmark executes an arbitrary gm utility command (e.g.  convert)  for
   one  or more loops, and/or a specified execution time, and reports many
   execution metrics.  For builds using OpenMP,  a  mode  is  provided  to
   execute  the benchmark with an increasing number of threads and provide
   a  report  of  speedup  and  multi-thread  execution  efficiency.    If
   benchmark is used to execute a command without any additional benchmark
   options, then the command is run once.

EXAMPLES

   To obtain benchmark information for a single execution of a command:

       gm benchmark convert input.ppm -gaussian 0x1 output.ppm

   To obtain benchmark information from 100 iterations of the command:

       gm benchmark -iterations 100 convert input.ppm \
         -gaussian 0x1 output.ppm

   To obtain benchmark  information  by  iterating  the  command  until  a
   specified amount of time (in seconds) has been consumed:

       gm benchmark -duration 30 convert input.ppm \
         -gaussian 0x1 output.ppm

   To  obtain  a  full  performance  report  with  an increasing number of
   threads (1-32 threads, stepping the number  of  threads  by  four  each
   time):

       gm benchmark -duration 3 -stepthreads 4 convert \
         input.ppm -gaussian 0x2 output.ppm

   Here is the interpretation of the output:

       threads - number of threads used.
       iter - number of command iterations executed.
       user - total user time consumed.
       total - total elapsed time consumed.
       iter/s - number of command iterations per second.
       iter/cpu - amount of CPU time consumed per iteration.
       speedup - speedup compared with one thread.
       karp-flatt - Karp-Flatt measure of speedup efficiency.

   Please  note that the reported "speedup" is based on the execution time
   of just one thread.  A preliminary warm-up pass is used  before  timing
   the first loop in order to ensure that the CPU is brought out of power-
   saving modes and that system caches are warmed up.   Most  modern  CPUs
   provide  a "turbo" mode where the CPU clock speed is increased (e.g. by
   a factor of two) when only one or two cores are  active.   If  the  CPU
   grows  excessively  hot (due to insufficient cooling), then it may dial
   back its clock rates as a form of thermal  management.   These  factors
   result in an under-reporting of speedup compared to if "turbo" mode was
   disabled and the CPU does not need to worry about  thermal  management.
   The  powertop  utility available under Linux and Solaris provides a way
   to observe CPU core clock rates while a benchmark is running.

OPTIONS

    Options are processed from left to right and must  appear  before  any
   argument.

   -duration duration
          duration  to  run benchmark Specify the number of seconds to run
          the benchmark. The command  is  executed  repeatedly  until  the
          specified amount of time has elapsed.

   -help

          Prints benchmark command help.

   -iterations loops
          number of command iterations Specify the number of iterations to
          run the benchmark. The command is executed repeatedly until  the
          specified number of iterations has been reached.

   -rawcsv
          Print  results  in CSV format Print results in a comma-separated
          value (CSV) format which  is  easy  to  parse  for  plotting  or
          importing  into  a spreadsheet or database.  The values reported
          are threads, iterations, user_time, and elapsed_time.

   -stepthreads step
          execute a per-thread benchmark ramp
           Execute a per-thread benchmark ramp, incrementing the number of
          threads at each step by the specified value.  The maximum number
          of  threads  is  taken   from   the   standard   OMP_NUM_THREADS
          environment variable.

GM COMPARE

   compare  compares  two  similar  images  using  a specified statistical
   method (see -metric) and/or by writing a difference image (-file), with
   the  altered pixels annotated using a specified method (see -highlight-
   style)  and  color  (see  -highlight-color).  Reference-image  is   the
   original  image  and  compare-image  is the (possibly) altered version,
   which should have the same dimensions as reference-image.

EXAMPLES

   To compare  two  images  using  Mean  Square  Error  (MSE)  statistical
   analysis use:

       gm compare -metric mse original.miff compare.miff

   To create an annotated difference image use:

       gm compare -highlight-style assign -highlight-color purple \
         -file diff.miff original.miff compare.miff

OPTIONS

   Options  are processed in command line order. Any option you specify on
   the command line remains in effect only for  the  image  that  follows.
   All options are reset to their default values after each image is read.

   For a more detailed description of each option, see Options, above.

   -authenticate <string>
          decrypt image with this password

   -colorspace <value>
          the type of colorspace

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -display <host:display[.screen]>
          specifies the X server to contact

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -file <filename>
          write annotated difference image to file

   -help  print usage instructions

   -highlight-color <color>
          pixel annotation color

   -highlight-style <style>
          pixel annotation style

   -interlace <type>
          the type of interlacing scheme

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -log <string>
          Specify format for debug log

   -matte store matte channel if the image has one

   -maximum-error <limit>
          specifies the maximum amount of total image error

   -metric <metric>
          comparison metric (MAE, MSE, PAE, PSNR, RMSE)

   -monitor
          show progress indication

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -size <width>x<height>{+offset}
          width and height of the image

   -type <type>
          the image type

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

          For a more detailed description of  each  option,  see  Options,
          above.

GM COMPOSITE

   composite  composites  (combines)  images  to create new images.  base-
   image is the base image and change-image contains the changes.   ouput-
   image  is  the  result,  and  normally has the same dimensions as base-
   image.

   The optional mask-image can be used to provide opacity information  for
   change-image  when it has none or if you want a different mask.  A mask
   image is typically grayscale and the same size as base-image. If  mask-
   image  is not grayscale, it is converted to grayscale and the resulting
   intensities are used as opacity information.

EXAMPLES

   To composite an image of a cockatoo with a perch, use:

       gm composite cockatoo.miff perch.ras composite.miff

   To compute the difference between images in a series, use:

       gm composite -compose difference series.2 series.1
                 difference.miff

   To composite an image of a cockatoo with a perch starting  at  location
   (100,150), use:

       gm composite -geometry +100+150 cockatoo.miff
                 perch.ras composite.miff

   To tile a logo across your image of a cockatoo, use

       gm convert +shade 30x60 cockatoo.miff mask.miff
       gm composite -compose bumpmap -tile logo.png
                 cockatoo.miff mask.miff composite.miff

   To composite a red, green, and blue color plane into a single composite
   image, try

       gm composite -compose CopyGreen green.png red.png
                 red-green.png
       gm composite -compose CopyBlue blue.png red-green.png
                 gm composite.png

OPTIONS

   Options are processed in command line order. Any option you specify  on
   the  command  line  remains  in effect only for the image that follows.
   All options are reset to their default values after each image is read.

   For a more detailed description of each option, see Options, above.

   -authenticate <string>
          decrypt image with this password

   -background <color>
          the background color

   -blue-primary <x>,<y>
          blue chromaticity primary point

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -compose <operator>
          the type of image composition

   -compress <type>
          the type of image compression

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -displace <horizontal scale>x<vertical scale>
          shift image pixels as defined by a displacement map

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dissolve <percent>
          dissolve an image into another by the given percent

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -encoding <type>
          specify the text encoding

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -filter <type>
          use this type of filter when resizing an image

   -font <name>
          use this font when annotating the image with text

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -gravity <type>
          direction primitive  gravitates to when annotating the image.

   -green-primary <x>,<y>
          green chromaticity primary point

   -help  print usage instructions

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -limit <type> <value>
          Disk, File,  Map,  Memory,  Pixels,  Width,  Height  or  Threads
          resource limit

   -log <string>
          Specify format for debug log

   -matte store matte channel if the image has one

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -negate
          replace every pixel with its complementary color

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   -profile <filename>
          add ICM, IPTC, or generic profile  to image

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -recolor <matrix>
          apply a color translation matrix to image channels

   -red-primary <x>,<y>
          red chromaticity primary point

   -render
          render vector operations

   -repage  <width>x<height>+xoff+yoff[!]
          Adjust image page offsets

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

   -rotate <degrees>{<}{>}
          rotate the image

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scene <value>
          set scene number

   -set <attribute> <value>
          set an image attribute

   +set <attribute>
          unset an image attribute

   -sharpen <radius>{x<sigma>}
          sharpen the image

   -size <width>x<height>{+offset}
          width and height of the image

   -stegano <offset>
          hide watermark within an image

   -stereo
          composite two images to create a stereo anaglyph

   -strip remove all profiles and text attributes from the image

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -units <type>
          the units of image resolution

   -unsharp <radius>{x<sigma>}{+<amount>}{+<threshold>}
          sharpen the image with an unsharp mask operator

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -watermark <brightness>x<saturation>
          percent brightness and saturation of a watermark

   -white-point <x>,<y>
          chromaticity white point

   -write <filename>
          write an intermediate image [convert, composite]

          For  a  more  detailed  description of each option, see Options,
          above.

GM CONJURE

   The Magick scripting language (MSL) will primarily benefit  those  that
   want  to  accomplish  custom  image processing tasks but do not wish to
   program, or those that do not have access to a Perl  interpreter  or  a
   compiler.   The  interpreter  is  called conjure and here is an example
   script:

       <?xml version="1.0" encoding="UTF-8"?>
       <image size="400x400" >
         <read filename="image.gif" />
         <get width="base-width" height="base-height" />
         <resize geometry="%[dimensions]" />
         <get width="width" height="height" />
         <print output=
           "Image sized from %[base-width]x%[base-height]
            to %[width]x%[height].\n" />
         <write filename="image.png" />
       </image>

   invoked with

       gm conjure -dimensions 400x400 incantation.msl

   All operations will closely  follow  the  key/value  pairs  defined  in
   PerlMagick, unless otherwise noted.

OPTIONS

   Options  are processed in command line order. Any option you specify on
   the command line remains in effect until it is  explicitly  changed  by
   specifying  the  option  again  with  a  different  effect, or if it is
   changed by a statement in the scripting language.

   You can define your own keyword/value pairs on the command  line.   The
   script  can  then use this information when setting values by including
   %[keyword] in the string.  For example, if  you  included  "-dimensions
   400x400"  on  the  command  line, as illustrated above, then any string
   containing  "%[dimensions]"  would  have  400x400   substituted.    The
   "%[string]"   can   be   used   either   an   entire  string,  such  as
   geometry="%[dimensions]"  or  as  a  part   of   a   string   such   as
   filename="%[basename].png".

   The keyword can be any string except for the following reserved strings
   (in any upper, lower, or mixed case variant): debug, help, and verbose,
   whose usage is described below.

   The  value  can  be  any  string.   If  either the keyword or the value
   contains white space or any symbols that have special meanings to  your
   shell  such  as "#", "|", or "%", enclose the string in quotation marks
   or use "\" to escape the white space and special symbols.

   Keywords and values are case dependent.  "Key", "key", and "KEY"  would
   be three different keywords.

   For a more detailed description of each option, see Options, above.

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -help  print usage instructions

   -log <string>
          Specify format for debug log

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

MAGICK SCRIPTING LANGUAGE

   The  Magick  Scripting  Language  (MSL) presently defines the following
   elements and their attributes:

           <image>

                background, color, id, size

                Define a new image object.  </image> destroys it.  Because
                of  this,  if  you  wish to reference multiple "subimages"
                (aka pages or layers), you can  embed  one  image  element
                inside of another. For example:

                    <image>
                    <read filename="input.png" />
                    <get width="base-width" height="base-height" />
                    <image height="base-height" width="base-width">
                    <image />
                    <write filename="output.mng" />
                    </image>

                    <image size="400x400" />

           <group>

                Define  a  new group of image objects.  By default, images
                are only valid for the life of their <image>element.

                    <image>   -- creates the image
                    .....     -- do stuff with it
                    </image>  -- dispose of the image

                However, in a group, all images in that  group  will  stay
                around for the life of the group:

                    <group>                           -- start a group
                        <image>                       -- create an image
                        ....                          -- do stuff
                        </image>                      -- NOOP
                        <image>                        --  create  another
                image
                        ....                          -- do more stuff
                        </image>                      -- NOOP
                        <write filename="image.mng" />  -- output
                    </group>                          -- dispose  of  both
                images

           <read>

                    filename

                Read a new image from a disk file.

                    <read filename="image.gif" />

                To read two images use

                    <read filename="image.gif" />
                    <read filename="image.png />

           <write>

                    filename
                Write  the  image(s) to disk, either as a single multiple-
                image file or multiple ones if necessary.

                     <write filename=image.tiff" />

           <get>

                Get   any    attribute    recognized    by    PerlMagick's
                GetAttribute()  and  stores  it  as an image attribute for
                later use. Currently only width and height are supported.

                    <get width="base-width" height="base-height" />
                    <print  output="Image  size  is  %[base-width]x%[base-
                height].\n" />

           <set>

                background,  bordercolor,  clip-mask, colorspace, density,
                magick, mattecolor, opacity.  Set an attribute  recognized
                by PerlMagick's GetAttribute().
           <profile>

                    [profilename]

                Read  one  or more IPTC, ICC or generic profiles from file
                and assign to image

                    <profile iptc="profile.iptc" generic="generic.dat" />

                To remove a specified profile use "!" as the filename eg

                    <profile icm="!" iptc="profile.iptc" />

           <border>

                    fill, geometry, height, width
           <blur>

                    radius, sigma
           <charcoal>

                    radius, sigma
           <chop>

                    geometry, height, width, x, y
           <crop>

                    geometry, height, width, x, y
           <composite>

                    compose, geometry, gravity, image, x, y

                    <?xml version="1.0" encoding="UTF-8"?>
                    <group>
                        <image id="image_01">
                            <read filename="cloud3.gif"/>
                            <resize geometry="250x90"/>
                        </image>
                        <image id="image_02">
                            <read filename="cloud4.gif"/>
                            <resize geometry="190x100"/>
                        </image>
                        <image>
                            <read filename="background.jpg"/>
                            <composite                    image="image_01"
                geometry="+740+470"/>
                            <composite                    image="image_02"
                geometry="+390+415"/>
                        </image>
                        <write filename="result.png"/>
                    </group>

           <despeckle>

           <emboss>

                    radius, sigma
           <enhance>

           <equalize>

           <edge>

                    radius
           <flip>

           <flop>

           <frame>

                    fill, geometry, height, width, x, y, inner, outer
           <flatten>

           <get>

                    height, width
           <gamma>

                    red, green, blue
           <image>

                    background, color, id, size
           <implode>

                    amount
           <magnify>

           <minify>

           <medianfilter>

                    radius
           <normalize>

           <oilpaint>

                    radius
           <print>

                    output
           <profile>

                    [profilename]
           <read>

           <resize>

                    blur, filter, geometry, height, width
           <roll>

                    geometry, x, y
           <rotate>

                    degrees
           <reducenoise>

                    radius
           <sample>

                    geometry, height, width
           <scale>

                    geometry, height, width
           <sharpen>

                    radius, sigma
           <shave>

                    geometry, height, width
           <shear>

                    x, y
           <solarize>

                    threshold
           <spread>

                    radius
           <stegano>

                    image
           <stereo>

                    image
           <swirl>

                    degrees
           <texture>

                    image
           <threshold>

                    threshold
           <transparent>

                    color
           <trim>

GM CONVERT

   Convert converts an input file using one image format to an output file
   with  a  differing  image  format.  In addition, various types of image
   processing  can  be  performed  on  the  converted  image  during   the
   conversion  process.  Convert  recognizes  the  image formats listed in
   GraphicsMagick(1).

EXAMPLES

   To make a thumbnail of a JPEG image, use:

       gm convert -size 120x120 cockatoo.jpg -resize 120x120
               +profile "*" thumbnail.jpg

   In this example, '-size 120x120' gives a hint to the JPEG decoder  that
   the  image  is  going  to  be downscaled to 120x120, allowing it to run
   faster by avoiding returning full-resolution images  to  GraphicsMagick
   for the subsequent resizing operation.  The ´-resize 120x120' specifies
   the desired dimensions of the output image.  It will be scaled  so  its
   largest  dimension  is 120 pixels.  The ´+profile "*"' removes any ICM,
   EXIF, IPTC, or other profiles that might be present in  the  input  and
   aren't needed in the thumbnail.

   To convert a MIFF image of a cockatoo to a SUN raster image, use:

       gm convert cockatoo.miff sun:cockatoo.ras

   To  convert  a  multi-page PostScript document to individual FAX pages,
   use:

       gm convert -monochrome document.ps fax:page

   To convert a TIFF image to a PostScript A4 page with the image  in  the
   lower left-hand corner, use:

       gm convert -page A4+0+0 image.tiff document.ps

   To  convert  a  raw  Gray  image  with  a 128 byte header to a portable
   graymap, use:

       gm convert -depth 8 -size 768x512+128 gray:raw
               image.pgm

   In this example, "raw" is the input file.  Its format is "gray" and  it
   has  the  dimensions  and number of header bytes specified by the -size
   option and the sample depth specified by the -depth option.  The output
   file is "image.pgm".  The suffix ".pgm" specifies its format.

   To convert a Photo CD image to a TIFF image, use:

       gm convert -size 1536x1024 img0009.pcd image.tiff
       gm convert img0009.pcd[4] image.tiff

   To create a visual image directory of all your JPEG images, use:

       gm convert 'vid:*.jpg' directory.miff

   To  annotate  an  image  with  blue  text  using font 12x24 at position
   (100,100), use:

       gm convert -font helvetica -fill blue
               -draw "text 100,100 Cockatoo"
               bird.jpg bird.miff

   To tile a 640x480 image with a JPEG texture with bumps use:

       gm convert -size 640x480 tile:bumps.jpg tiled.png

   To surround an icon with an ornamental border to  use  with  Mosaic(1),
   use:

       gm convert -mattecolor "#697B8F" -frame 6x6 bird.jpg
               icon.png

   To create a MNG animation from a DNA molecule sequence, use:

       gm convert -delay 20 dna.* dna.mng

OPTIONS

   Options  are processed in command line order. Any option you specify on
   the command line remains in effect for the set of images that  follows,
   until  the  set is terminated by the appearance of any option or -noop.
   Some options only affect the decoding of images  and  others  only  the
   encoding.  The latter can appear after the final group of input images.

   For a more detailed description of each option, see Options, above.

   -adjoin
          join images into a single multi-image file

   -affine <matrix>
          drawing transform matrix

   -antialias
          remove pixel aliasing

   -append
          append a set of images

    -asc-cdl <spec>
          apply ASC CDL color transform

   -authenticate <string>
          decrypt image with this password

   -auto-orient
          orient (rotate) image so it is upright

   -average
          average a set of images

   -background <color>
          the background color

   -black-threshold red[,green][,blue][,opacity]
          pixels below the threshold become black

   -blue-primary <x>,<y>
          blue chromaticity primary point

   -blur <radius>{x<sigma>}
          blur the image with a Gaussian operator

   -border <width>x<height>
          surround the image with a border of color

   -bordercolor <color>
          the border color

   -box <color>
          set the color of the annotation bounding box

   -channel <type>
          the type of channel

   -charcoal <factor>
          simulate a charcoal drawing

   -chop <width>x<height>{+-}<x>{+-}<y>{%}
          remove pixels from the interior of an image

   -clip  apply the clipping path, if one is present

   -coalesce
          merge a sequence of images

   -colorize <value>
          colorize the image with the pen color

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -compose <operator>
          the type of image composition

   -compress <type>
          the type of image compression

   -contrast
          enhance or reduce the image contrast

   -convolve <kernel>
          convolve image with the specified convolution kernel

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -cycle <amount>
          displace image colormap by amount

   -debug <events>
          enable debug printout

   -deconstruct
          break down an image sequence into constituent parts

   -define <key>{=<value>},...
          add coder/decoder specific options

   -delay <1/100ths of a second>
          display the next image after pausing

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -despeckle
          reduce the speckles within an image

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -draw <string>
          annotate an image with one or more graphic primitives

   -edge <radius>
          detect edges within an image

   -emboss <radius>
          emboss an image

   -encoding <type>
          specify the text encoding

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -enhance
          apply a digital filter to enhance a noisy image

   -equalize
          perform histogram equalization to the image

   -extent <width>x<height>{+-}<x>{+-}<y>
          composite image on background color canvas image

   -fill <color>
          color to use when filling a graphic primitive

   -filter <type>
          use this type of filter when resizing an image

   -flatten
          flatten a sequence of images

   -flip  create a "mirror image"

   -flop  create a "mirror image"

   -font <name>
          use this font when annotating the image with text

   -format <string>
          output formatted image characteristics

   -frame <width>x<height>+<outer bevel width>+<inner bevel width>
          surround the image with an ornamental border

   -fuzz <distance>{%}
          colors within this Euclidean distance are considered equal

   -gamma <value>
          level of gamma correction

   -gaussian <radius>{x<sigma>}
          blur the image with a Gaussian operator

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -gravity <type>
          direction primitive  gravitates to when annotating the image.

   -green-primary <x>,<y>
          green chromaticity primary point

   -hald-clut <clut>
          apply a Hald CLUT to the image

   -help  print usage instructions

   -implode <factor>
          implode image pixels about the center

   -intent <type>
          use this type of rendering intent when managing the image color

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -lat <width>x<height>{+-}<offset>{%}
          perform local adaptive thresholding

   -level <black_point>{,<gamma>}{,<white_point>}{%}
          adjust the level of image contrast

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -list <type>
          the type of list

   -log <string>
          Specify format for debug log

   -loop <iterations>
          add Netscape loop extension to your GIF animation

   -magnify
          magnify the image

   -map <filename>
          choose a particular set of colors from this image

   -mask <filename>
          Specify a clipping mask

   -matte store matte channel if the image has one

   -mattecolor <color>
          specify the color to be used with the -frame option

   -median <radius>
          apply a median filter to the image

   -minify <factor>
          minify the image

   -modulate brightness[,saturation[,hue]]
          vary the brightness, saturation, and hue of an image

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -morph <frames>
          morphs an image sequence

   -mosaic
          create a mosaic from an image or an image sequence

   -motion-blur <radius>{x<sigma>}{+angle}
          Simulate motion blur

   -negate
          replace every pixel with its complementary color

   -noise <radius|type>
          add or reduce noise in an image

   -noop  NOOP (no option)

   -normalize
          transform image to span the full range of color values

   -opaque <color>
          change this color to the pen color within the image

   -operator channel operator rvalue[%]
          apply a mathematical, bitwise, or value  operator  to  an  image
          channel

   -ordered-dither <channeltype> <NxN>
          ordered dither the image

   -orient <orientation>
          Set the image orientation attribute

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   -paint <radius>
          simulate an oil painting

   -pen <color>
          (This option has been replaced by the -fill option)

   -ping  efficiently determine image characteristics

   -pointsize <value>
          pointsize of the PostScript, X11, or TrueType font

   -preview <type>
          image preview type

   -process <command>
          process a sequence of images using a process module

   -profile <filename>
          add ICM, IPTC, or generic profile  to image

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -raise <width>x<height>
          lighten or darken image edges

   -random-threshold <channeltype> <LOWxHIGH>
          random threshold the image

   -recolor <matrix>
          apply a color translation matrix to image channels

   -red-primary <x>,<y>
          red chromaticity primary point

   -region <width>x<height>{+-}<x>{+-}<y>
          apply options to a portion of the image

   -render
          render vector operations

   -repage  <width>x<height>+xoff+yoff[!]
          Adjust image page offsets

   -resample <horizontal>x<vertical>
          Resample image to specified horizontal and vertical resolution

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

   -roll {+-}<x>{+-}<y>
          roll an image vertically or horizontally

   -rotate <degrees>{<}{>}
          rotate the image

   -sample <geometry>
          scale image using pixel sampling

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scale <geometry>
          scale the image.

   -scene <value>
          set scene number

   -set <attribute> <value>
          set an image attribute

   +set <attribute>
          unset an image attribute

   -segment <cluster threshold>x<smoothing threshold>
          segment an image

   -shade <azimuth>x<elevation>
          shade the image using a distant light source

   -sharpen <radius>{x<sigma>}
          sharpen the image

   -shave <width>x<height>{%}
          shave pixels from the image edges

   -shear <x degrees>x<y degrees>
          shear the image along the X or Y axis

   -size <width>x<height>{+offset}
          width and height of the image

   -solarize <factor>
          negate all pixels above the threshold level

   -spread <amount>
          displace image pixels by a random amount

   -strip remove all profiles and text attributes from the image

   -stroke <color>
          color to use when stroking a graphic primitive

   -strokewidth <value>
          set the stroke width

   -swirl <degrees>
          swirl image pixels about the center

   -texture <filename>
          name of texture to tile onto the image background

   -threshold <value>{%}
          threshold the image

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

   -tile <filename>
          tile image when filling a graphic primitive

   -transform
          transform the image

   -transparent <color>
          make this color transparent within the image

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -units <type>
          the units of image resolution

   -unsharp <radius>{x<sigma>}{+<amount>}{+<threshold>}
          sharpen the image with an unsharp mask operator

   -use-pixmap
          use the pixmap

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -view <string>
          FlashPix viewing parameters

   -virtual-pixel <method>
          specify contents of "virtual pixels"

   -wave <amplitude>x<wavelength>
          alter an image along a sine wave

   -white-point <x>,<y>
          chromaticity white point

   -white-threshold red[,green][,blue][,opacity]
          pixels above the threshold become white

   -write <filename>
          write an intermediate image [convert, composite]

          For  a  more  detailed  description of each option, see Options,
          above.

GM DISPLAY

   Display is a machine  architecture  independent  image  processing  and
   display  program.  It  can  display  an image on any workstation screen
   running an X server. Display can  read  and  write  many  of  the  more
   popular image formats (e.g. JPEG, TIFF, PNM, Photo CD, etc.).

   With display, you can perform these functions on an image:

            o  load an image from a file
            o  display the next image
            o  display the former image
            o  display a sequence of images as a slide show
            o  write the image to a file
            o  print the image to a PostScript printer
            o  delete the image file
            o  create a Visual Image Directory
            o   select  the  image to display by its thumbnail rather than
           name
            o  undo last image transformation
            o  copy a region of the image
            o  paste a region to the image
            o  restore the image to its original size
            o  refresh the image
            o  half the image size
            o  double the image size
            o  resize the image
            o  crop the image
            o  cut the image
            o  flop image in the horizontal direction
            o  flip image in the vertical direction
            o  rotate the image 90 degrees clockwise
            o  rotate the image 90 degrees counter-clockwise
            o  rotate the image
            o  shear the image
            o  roll the image
            o  trim the image edges
            o  invert the colors of the image
            o  vary the color brightness
            o  vary the color saturation
            o  vary the image hue
            o  gamma correct the image
            o  sharpen the image contrast
            o  dull the image contrast
            o  perform histogram equalization on the image
            o  perform histogram normalization on the image
            o  negate the image colors
            o  convert the image to grayscale
            o  set the maximum number of unique colors in the image
            o  reduce the speckles within an image
            o  eliminate peak noise from an image
            o  detect edges within the image
            o  emboss an image
            o  segment the image by color
            o  simulate an oil painting
            o  simulate a charcoal drawing
            o  annotate the image with text
            o  draw on the image
            o  edit an image pixel color
            o  edit the image matte information
            o  composite an image with another
            o  add a border to the image
            o  surround image with an ornamental border
            o  apply image processing techniques to a region of interest
            o  display information about the image
            o  zoom a portion of the image
            o  show a histogram of the image
            o  display image to background of a window
            o  set user preferences
            o  display information about this program
            o  discard all images and exit program
            o  change the level of magnification
            o  display images specified by a World Wide Web (WWW)  uniform
           resource locator (URL)

EXAMPLES

   To  scale an image of a cockatoo to exactly 640 pixels in width and 480
   pixels in height and position the window at location (200,200), use:

       gm display -geometry 640x480+200+200! cockatoo.miff

   To display an image of a  cockatoo  without  a  border  centered  on  a
   backdrop, use:

       gm display +borderwidth -backdrop cockatoo.miff

   To tile a slate texture onto the root window, use:

       gm display -size 1280x1024 -window root slate.png

   To display a visual image directory of all your JPEG images, use:

       gm display 'vid:*.jpg'

   To  display  a  MAP image that is 640 pixels in width and 480 pixels in
   height with 256 colors, use:

       gm display -size 640x480+256 cockatoo.map

   To display an image of a cockatoo specified with a World Wide Web (WWW)
   uniform resource locator (URL), use:

       gm display ftp://wizards.dupont.com/images/cockatoo.jpg

   To display histogram of an image, use:

       gm gm convert file.jpg HISTOGRAM:- | gm display -

OPTIONS

   Options  are processed in command line order. Any option you specify on
   the command line remains in effect until it is  explicitly  changed  by
   specifying  the  option  again  with a different effect. For example to
   display three images, the first with 32  colors,  the  second  with  an
   unlimited number of colors, and the third with only 16 colors, use:

       gm display -colors 32 cockatoo.miff -noop duck.miff
                    -colors 16 macaw.miff

   Display  options  can appear on the command line or in your X resources
   file. See X(1). Options on the command line supersede values  specified
   in your X resources file.

   For a more detailed description of each option, see Options, above.

   -authenticate <string>
          decrypt image with this password

   -backdrop
          display the image centered on a backdrop.

   -background <color>
          the background color

   -border <width>x<height>
          surround the image with a border of color

   -bordercolor <color>
          the border color

   -borderwidth <geometry>
          the border width

   -colormap <type>
          define the colormap type

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -compress <type>
          the type of image compression

   -contrast
          enhance or reduce the image contrast

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -delay <1/100ths of a second>
          display the next image after pausing

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -despeckle
          reduce the speckles within an image

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -edge <radius>
          detect edges within an image

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -enhance
          apply a digital filter to enhance a noisy image

   -filter <type>
          use this type of filter when resizing an image

   -flip  create a "mirror image"

   -flop  create a "mirror image"

   -font <name>
          use this font when annotating the image with text

   -foreground <color>
          define the foreground color

   -frame <width>x<height>+<outer bevel width>+<inner bevel width>
          surround the image with an ornamental border

   -gamma <value>
          level of gamma correction

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -help  print usage instructions

   -iconGeometry <geometry>
          specify the icon geometry

   -iconic
          iconic animation

   -immutable
          make image immutable

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -log <string>
          Specify format for debug log

   -magnify <factor>
          magnify the image

   -map <type>
          display image using this type.

   -matte store matte channel if the image has one

   -mattecolor <color>
          specify the color to be used with the -frame option

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -name  name an image

   -negate
          replace every pixel with its complementary color

   -noop  NOOP (no option)

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   +progress
          disable progress monitor and busy cursor

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -raise <width>x<height>
          lighten or darken image edges

   -remote
          perform a X11 remote operation

   -roll {+-}<x>{+-}<y>
          roll an image vertically or horizontally

   -rotate <degrees>{<}{>}
          rotate the image

   -sample <geometry>
          scale image using pixel sampling

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scenes <value-value>
          range of image scene numbers to read

   -set <attribute> <value>
          set an image attribute

   +set <attribute>
          unset an image attribute

   -segment <cluster threshold>x<smoothing threshold>
          segment an image

   -shared-memory
          use shared memory

   -sharpen <radius>{x<sigma>}
          sharpen the image

   -size <width>x<height>{+offset}
          width and height of the image

   -text-font <name>
          font for writing fixed-width text

   -texture <filename>
          name of texture to tile onto the image background

   -title <string>
          assign title to displayed image [animate, display, montage]

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -update <seconds>
           detect when image file is modified and redisplay.

   -use-pixmap
          use the pixmap

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -visual <type>
          animate images using this X visual type

   -window <id>
          make image the background of a window

   -window-group
          specify the window group

   -write <filename>
          write the image to a file [display]

          For a more detailed description of  each  option,  see  Options,
          above.

MOUSE BUTTONS

   The  effects of each button press is described below. Three buttons are
   required. If you have a two button mouse, button 1 and 3 are  returned.
   Press ALT and button 3 to simulate button 2.

   1        Press this button to map or unmap the Command widget . See the
          next section for more information about the Command widget.

   2       Press and drag to define a region of the image to magnify.

   3       Press and drag to  choose  from  a  select  set  of  display(1)
          commands.  This  button  behaves  differently if the image being
          displayed is a visual image directory. Choose a particular  tile
          of  the  directory  and  press  this button and drag to select a
          command from a pop-up menu.  Choose from these menu items:

              Open
              Next
              Former
              Delete
              Update

          If you choose  Open,  the  image  represented  by  the  tile  is
          displayed.  To return to the visual image directory, choose Next
          from the Command widget (refer to  Command  Widget).   Next  and
          Former  moves  to  the next or former image respectively. Choose
          Delete to delete a particular image tile. Finally, choose Update
          to synchronize all the image tiles with their respective images.
          See montage and miff for more details.

COMMAND WIDGET

   The Command widget lists a number of sub-menus and commands. They are

       File

       Open...
       Next
       Former
       Select...
       Save...
       Print...
       Delete...
       Canvas...
       Visual Directory...
       Quit

       Edit

       Undo
       Redo
       Cut
       Copy
       Paste

       View

       Half Size
       Original Size
       Double Size
       Resize...
       Apply
       Refresh
       Restore

       Transform

       Crop
       Chop
       Flop
       Flip
       Rotate Right
       Rotate Left
       Rotate...
       Shear...
       Roll...
       Trim Edges

       Enhance

       Hue...
       Saturation...
       Brightness...
       Gamma...
       Spiff...
       Dull
       Equalize
       Normalize
       Negate
       GRAYscale
       Quantize...

       Effects

       Despeckle
       Emboss
       Reduce Noise
       Add Noise
       Sharpen...
       Blur...
       Threshold...
       Edge Detect...
       Spread...
       Shade...
       Raise...
       Segment...

       F/X

       Solarize...
       Swirl...
       Implode...
       Wave...
       Oil Paint...
       Charcoal Draw...

       Image Edit

       Annotate...
       Draw...
       Color...
       Matte...
       Composite...
       Add Border...
       Add Frame...
       Comment...
       Launch...
       Region of Interest...

       Miscellany

       Image Info
       Zoom Image
       Show Preview...
       Show Histogram
       Show Matte
       Background...
       Slide Show
       Preferences...

       Help

       Overview
       Browse Documentation
       About Display

   Menu  items  with  a  indented  triangle  have  a  sub-menu.  They  are
   represented  above  as  the  indented items. To access a sub-menu item,
   move the pointer to the appropriate menu and press button 1  and  drag.
   When  you  find  the  desired sub-menu item, release the button and the
   command is executed.  Move the pointer away from the  sub-menu  if  you
   decide not to execute a particular command.

KEYBOARD ACCELERATORS

   Accelerators  are  one  or  two  key  presses  that effect a particular
   command.  The keyboard accelerators that display understands is:

       Ctl+O     Press to load an image from a file.
       space     Press to display the next image.

   If the image is a multi-paged document such as a  PostScript  document,
   you  can  skip  ahead  several  pages  by preceding this command with a
   number.  For example to display the  fourth  page  beyond  the  current
   page, press 4space.

       backspace Press to display the former image.

   If  the  image is a multi-paged document such as a PostScript document,
   you can skip behind several pages by  preceding  this  command  with  a
   number.   For  example to display the fourth page preceding the current
   page, press 4n.

       Ctl-S    Press to save the image to a file.
       Ctl-P    Press to print the image to a
                PostScript printer.
       Ctl-D    Press to delete an image file.
       Ctl-N    Press to create a blank canvas.
       Ctl-Q    Press to discard all images and exit program.
       Ctl+Z    Press to undo last image transformation.
       Ctl+R    Press to redo last image transformation.
       Ctl-X    Press to cut a region of
                the image.
       Ctl-C    Press to copy a region of
                the image.
       Ctl-V    Press to paste a region to
                the image.
       <        Press to halve the image size.
       .        Press to return to the original image size.
       >        Press to double the image size.
       %        Press to resize the image to a width and height
                you specify.
       Cmd-A    Press to make any image transformations
                permanent.
                By default, any image size transformations are
                applied to the original image to create the
                image displayed on the X server.  However, the
                transformations are not permanent (i.e. the
                original image does not change size only the
                X image does). For example, if you press ">"
                the X image will appear to double in size, but
                the original image will in fact remain the same
                size.  To force the original image to double in
                size, press ">" followed by "Cmd-A".
       @        Press to refresh the image window.
       C        Press to crop the image.
       [        Press to chop the image.
       H        Press to flop image in the horizontal direction.
       V        Press to flip image in the vertical direction.
       /        Press to rotate the image 90 degrees clockwise.
       \        Press to rotate the image 90 degrees
                counter-clockwise.
       *        Press to rotate the image
                the number of degrees you specify.
       S        Press to shear the image the number of degrees
                you specify.
       R        Press to roll the image.
       T        Press to trim the image edges.
       Shft-H   Press to vary the color hue.
       Shft-S   Press to vary the color saturation.
       Shft-L   Press to vary the image brightness.
       Shft-G   Press to gamma correct the image.
       Shft-C   Press to spiff up the image contrast.
       Shft-Z   Press to dull the image contrast.
       =        Press to perform histogram equalization on
                the image.
       Shft-N   Press to perform histogram normalization on
                the image.
       Shft-~   Press to negate the colors of the image.
       .        Press to convert the image colors to gray.
       Shft-#   Press to set the maximum number of unique
                colors in the image.
       F2       Press to reduce the speckles in an image.
       F2       Press to emboss an image.
       F4       Press to eliminate peak noise from an image.
       F5       Press to add noise to an image.
       F6       Press to sharpen an image.
       F7       Press to blur image an image.
       F8       Press to threshold the image.
       F9       Press to detect edges within an image.
       F10      Press to displace pixels by a random amount.
       F11      Press to shade the image using a distant light
                source.
       F12      Press to lighten or darken image edges to
                create a 3-D effect.
       F13      Press to segment the image by color.
       Meta-S   Press to swirl image pixels about the center.
       Meta-I   Press to implode image pixels about the center.
       Meta-W   Press to alter an image along a sine wave.
       Meta-P   Press to simulate an oil painting.
       Meta-C   Press to simulate a charcoal drawing.
       Alt-X    Press to composite the image
                with another.
       Alt-A    Press to annotate the image with text.
       Alt-D    Press to draw a line on the image.
       Alt-P    Press to edit an image pixel color.
       Alt-M    Press to edit the image matte information.
       Alt-X    Press to composite the image with another.
       Alt-A    Press to add a border to the image.
       Alt-F    Press to add a ornamental frame to the image.
       Alt-Shft-!   Press to add an image comment.
       Ctl-A    Press to apply image processing techniques to a
                region of interest.
       Shft-?   Press to display information about the image.
       Shft-+   Press to map the zoom image window.
       Shft-P   Press to preview an image enhancement, effect,
                or f/x.
       F1       Press to display helpful information about
                the "display" utility.
       Find     Press to browse documentation about
                GraphicsMagick.
       1-9      Press to change the level of magnification.

   Use the arrow keys to move the image one pixel up, down, left, or right
   within  the  magnify window. Be sure to first map the magnify window by
   pressing button 2.

   Press ALT and one of the arrow keys to trim off one pixel from any side
   of the image.

X RESOURCES

   Display  options  can  appear on the command line or in your X resource
   file. Options on the command line supersede values specified in your  X
   resource file. See X(1) for more information on X resources.

   Most  display  options  have  a  corresponding X resource. In addition,
   display uses the following X resources:

   background (class Background)
           Specifies the preferred color  to  use  for  the  Image  window
          background. The default is #ccc.

   borderColor (class BorderColor)
            Specifies  the  preferred  color  to  use for the Image window
          border. The default is #ccc.

   borderWidth (class BorderWidth)
           Specifies the width in pixels of the image window  border.  The
          default is 2.

   browseCommand (class browseCommand)
            Specifies  the  name  of the preferred browser when displaying
          GraphicsMagick documentation. The default is netscape %s.

   confirmExit (class ConfirmExit)
           Display pops up a dialog box to  confirm  exiting  the  program
          when  exiting  the  program.  Set this resource to False to exit
          without a confirmation.

   displayGamma (class DisplayGamma)
           Specifies the gamma of the X server.  You  can  apply  separate
          gamma  values  to the red, green, and blue channels of the image
          with  a  gamma  value  list  delineated   with   slashes   (i.e.
          1.7/2.3/1.2).  The default is 2.2.

   displayWarnings (class DisplayWarnings)
           Display pops up a dialog box whenever a warning message occurs.
          Set this resource to False to ignore warning messages.

   font (class FontList)
           Specifies the name of the  preferred  font  to  use  in  normal
          formatted text.  The default is 14 point Helvetica.

   font[1-9] (class Font[1-9])
           Specifies the name of the preferred font to use when annotating
          the image  window  with  text.  The  default  fonts  are  fixed,
          variable,  5x8,  6x10,  7x13bold, 8x13bold, 9x15bold, 10x20, and
          12x24.

   foreground (class Foreground)
           Specifies the preferred color to use for text within the  image
          window.  The default is black.

   gammaCorrect (class gammaCorrect)
            This  resource,  if  true,  will lighten or darken an image of
          known gamma to match the gamma  of  the  display  (see  resource
          displayGamma). The default is True.

   geometry (class Geometry)
            Specifies the preferred size and position of the image window.
          It is not necessarily obeyed by all window managers.

          Offsets, if present, are handled in X(1) style.   A  negative  x
          offset  is  measured  from  the  right edge of the screen to the
          right edge of the icon, and a negative y offset is measured from
          the bottom edge of the screen to the bottom edge of the icon.

   iconGeometry (class IconGeometry)
            Specifies  the  preferred size and position of the application
          when iconified.  It is not  necessarily  obeyed  by  all  window
          managers.

          Offsets,  if present, are handled in the same manner as in class
          Geometry.

   iconic (class Iconic)
            This  resource  indicates  that  you  would  prefer  that  the
          application's windows initially not be visible as if the windows
          had be immediately iconified by you. Window managers may  choose
          not to honor the application's request.

   magnify (class Magnify)
            specifies  an  integral  factor  by  which the image should be
          enlarged. The  default  is  3.   This  value  only  affects  the
          magnification window which is invoked with button number 3 after
          the image is displayed.

   matteColor (class MatteColor)
           Specify the color of windows. It is used for the backgrounds of
          windows,  menus,  and  notices. A 3D effect is achieved by using
          highlight and shadow colors derived  from  this  color.  Default
          value: #697B8F.

   name (class Name)
            This resource specifies the name under which resources for the
          application should be found. This resource is  useful  in  shell
          aliases  to  distinguish  between invocations of an application,
          without resorting to creating links to alter the executable file
          name. The default is the application name.

   pen[1-9] (class Pen[1-9])
            Specifies  the  color  of  the  preferred  font  to  use  when
          annotating the image window with text. The  default  colors  are
          black, blue, green, cyan, gray, red, magenta, yellow, and white.

   printCommand (class PrintCommand)
           This command is executed whenever Print is issued.  In general,
          it is the command to print PostScript to your  printer.  Default
          value: lp -c -s %i.

   sharedMemory (class SharedMemory)
            This  resource  specifies  whether  display should attempt use
          shared memory for pixmaps. GraphicsMagick must be compiled  with
          shared  memory support, and the display must support the MIT-SHM
          extension. Otherwise, this resource is ignored. The  default  is
          True.

   textFont (class textFont)
            Specifies  the  name  of  the  preferred  font to use in fixed
          (typewriter style) formatted  text.  The  default  is  14  point
          Courier.

   title (class Title)
            This  resource  specifies  the  title to be used for the image
          window. This information is sometimes used by a  window  manager
          to  provide  a header identifying the window. The default is the
          image file name.

   undoCache (class UndoCache)
           Specifies, in mega-bytes, the amount of memory in the undo edit
          cache.   Each  time you modify the image it is saved in the undo
          edit cache as long as memory is available. You can  subsequently
          undo  one  or  more  of these transformations. The default is 16
          Megabytes.

   usePixmap (class UsePixmap)
           Images are maintained as a XImage by default. Set this resource
          to  True  to  utilize  a  server  Pixmap instead. This option is
          useful if your image  exceeds  the  dimensions  of  your  server
          screen  and  you intend to pan the image. Panning is much faster
          with Pixmaps than  with  a  XImage.  Pixmaps  are  considered  a
          precious resource, use them with discretion.

          To  set  the  geometry  of the Magnify or Pan or window, use the
          geometry resource.  For example, to set the Pan window  geometry
          to 256x256, use:

              gm display.pan.geometry: 256x256

IMAGE LOADING

   To  select  an  image to display, choose Open of the File sub-menu from
   the  Command  widget.  A  file  browser  is  displayed.   To  choose  a
   particular  image  file, move the pointer to the filename and press any
   button. The filename is copied to the text window. Next, press Open  or
   press  the  RETURN key. Alternatively, you can type the image file name
   directly into  the  text  window.  To  descend  directories,  choose  a
   directory name and press the button twice quickly. A scrollbar allows a
   large list of filenames to be moved through  the  viewing  area  if  it
   exceeds the size of the list area.

   You can trim the list of file names by using shell globbing characters.
   For example, type *.jpg to list only files that end with .jpg.

   To select your image from the X server screen instead of from  a  file,
   Choose Grab of the Open widget.

VISUAL IMAGE DIRECTORY

   To create a Visual Image Directory, choose Visual Directory of the File
   sub-menu from the Command widget . A  file  browser  is  displayed.  To
   create  a  Visual  Image  Directory  from all the images in the current
   directory, press Directory or press the RETURN key.  Alternatively, you
   can select a set of image names by using shell globbing characters. For
   example, type *.jpg to include  only  files  that  end  with  .jpg.  To
   descend directories, choose a directory name and press the button twice
   quickly. A scrollbar allows a large  list  of  filenames  to  be  moved
   through the viewing area if it exceeds the size of the list area.

   After  you  select  a set of files, they are turned into thumbnails and
   tiled onto a single  image.  Now  move  the  pointer  to  a  particular
   thumbnail  and press button 3 and drag. Finally, select Open. The image
   represented by the thumbnail is displayed at its full size. Choose Next
   from  the  File  sub-menu of the Command widget to return to the Visual
   Image Directory.

IMAGE CUTTING

   Note that  cut  information  for  image  window  is  not  retained  for
   colormapped X server visuals (e.g. StaticColor, StaticColor, GRAYScale,
   PseudoColor).  Correct cutting behavior  may  require  a  TrueColor  or
   DirectColor visual or a Standard Colormap.

   To  begin,  press  choose  Cut  of  the  Edit sub-menu from the Command
   widget. Alternatively, press F3 in the image window.

   A small window appears showing the location of the cursor in the  image
   window.  You  are  now in cut mode. In cut mode, the Command widget has
   these options:

       Help
       Dismiss

   To define a cut region, press button 1 and  drag.  The  cut  region  is
   defined  by  a  highlighted  rectangle  that expands or contracts as it
   follows the pointer. Once  you  are  satisfied  with  the  cut  region,
   release  the button.  You are now in rectify mode. In rectify mode, the
   Command widget has these options:

       Cut
       Help
       Dismiss

   You can make adjustments by moving  the  pointer  to  one  of  the  cut
   rectangle  corners, pressing a button, and dragging. Finally, press Cut
   to commit your copy region. To exit without cutting  the  image,  press
   Dismiss.

IMAGE COPYING

   To  begin,  press  choose  Copy  of  the Edit sub-menu from the Command
   widget. Alternatively, press F4 in the image window.

   A small window appears showing the location of the cursor in the  image
   window.  You are now in copy mode. In copy mode, the Command widget has
   these options:

       Help
       Dismiss

   To define a copy region, press button 1 and drag. The  copy  region  is
   defined  by  a  highlighted  rectangle  that expands or contracts as it
   follows the pointer. Once you  are  satisfied  with  the  copy  region,
   release  the button.  You are now in rectify mode. In rectify mode, the
   Command widget has these options:

       Copy
       Help
       Dismiss

   You can make adjustments by moving the  pointer  to  one  of  the  copy
   rectangle corners, pressing a button, and dragging. Finally, press Copy
   to commit your copy region. To exit without copying  the  image,  press
   Dismiss.

IMAGE PASTING

   To  begin,  press  choose  Paste  of the Edit sub-menu from the Command
   widget. Alternatively, press F5 in the image window.

   A small window appears showing the location of the cursor in the  image
   window.  You are now in Paste mode. To exit immediately, press Dismiss.
   In Paste mode, the Command widget has these options:

       Operators

       over
       in
       out
       atop
       xor
       plus
       minus
       add
       subtract
       difference
       multiply
       bumpmap
       replace

       Help
       Dismiss

   Choose a composite operation from the Operators sub-menu of the Command
   widget.  How  each operator behaves is described below. image window is
   the image currently displayed on your X server and image is  the  image
   obtained with the File Browser widget.

   over     The  result  is  the union of the two image shapes, with image
          obscuring image window in the region of overlap.

   in      The result is simply image cut by the shape  of  image  window.
          None of the image data of image window is in the result.

   out     The resulting image is image with the shape of image window cut
          out.

   atop    The result is the  same  shape  as  image  window,  with  image
          obscuring image window where the image shapes overlap. Note this
          differs from over because the portion  of  image  outside  image
          window's shape does not appear in the result.

   xor      The  result is the image data from both image and image window
          that is outside the overlap region. The overlap region is blank.

   plus    The result is just the sum of the image data. Output values are
          cropped  to  the  maximum value (no overflow). This operation is
          independent of the matte channels.

   minus   The result of image - image window, with underflow  cropped  to
          zero.  The  matte  channel  is  ignored  (set  to  opaque,  full
          coverage).

   add     The result of image +  image  window,  with  overflow  wrapping
          around (mod MaxRGB+1).

   subtract
            The  result  of  image - image window, with underflow wrapping
          around (mod MaxRGB+1). The add and  subtract  operators  can  be
          used to perform reversible transformations.

   difference
            The  result  of  abs(image - image window). This is useful for
          comparing two very similar images.

   multiply
           The result of image * image window.  This  is  useful  for  the
          creation of drop-shadows.

   bumpmap
           The result of image window shaded by window.

   replace
          The  resulting  image is image window replaced with image.  Here
          the matte information is ignored.

          The image compositor requires a matte, or alpha channel  in  the
          image  for some operations. This extra channel usually defines a
          mask which represents a sort of a cookie-cutter for  the  image.
          This  is  the  case when matte is 255 (full coverage) for pixels
          inside the shape, zero outside, and between zero and 255 on  the
          boundary.  If  image  does  not  have  a  matte  channel,  it is
          initialized with 0 for any pixel  matching  in  color  to  pixel
          location (0,0), otherwise 255. See Matte Editing for a method of
          defining a matte channel.

          Note that matte information for image window is not retained for
          colormapped  X  server  visuals  (e.g. StaticColor, StaticColor,
          GrayScale,  PseudoColor).   Correct  compositing  behavior   may
          require   a  TrueColor  or  DirectColor  visual  or  a  Standard
          Colormap.

          Choosing a composite operator is optional. The default  operator
          is  replace.   However,  you must choose a location to composite
          your image and press button 1. Press and hold the button  before
          releasing  and  an  outline of the image will appear to help you
          identify your location.

          The actual colors of the pasted image  is  saved.  However,  the
          color  that  appears  in  image  window  may  be  different. For
          example, on a monochrome screen image window will  appear  black
          or  white even though your pasted image may have many colors. If
          the image is saved to a file it  is  written  with  the  correct
          colors.  To  assure  the  correct  colors are saved in the final
          image, any PseudoClass image is  promoted  to  DirectClass.   To
          force a PseudoClass image to remain PseudoClass, use -colors.

IMAGE CROPPING

   To  begin,  press choose Crop of the Transform submenu from the Command
   widget. Alternatively, press C in the image window.

   A small window appears showing the location of the cursor in the  image
   window.  You are now in crop mode. In crop mode, the Command widget has
   these options:

       Help
       Dismiss

   To define a cropping region, press button  1  and  drag.  The  cropping
   region  is defined by a highlighted rectangle that expands or contracts
   as it follows the pointer. Once you are  satisfied  with  the  cropping
   region,  release  the  button.  You are now in rectify mode. In rectify
   mode, the Command widget has these options:

       Crop
       Help
       Dismiss

   You can make adjustments by moving the pointer to one of  the  cropping
   rectangle corners, pressing a button, and dragging. Finally, press Crop
   to commit your cropping region. To exit  without  cropping  the  image,
   press Dismiss.

IMAGE CHOPPING

   An image is chopped interactively. There is no command line argument to
   chop an image. To begin, choose Chop of the Transform sub-menu from the
   Command widget. Alternatively, press [ in the Image window.

   You  are now in Chop mode. To exit immediately, press Dismiss.  In Chop
   mode, the Command widget has these options:

       Direction

       horizontal
       vertical

       Help
       Dismiss

   If the you choose the horizontal direction (this is the  default),  the
   area of the image between the two horizontal endpoints of the chop line
   is removed.  Otherwise, the area of the image between the two  vertical
   endpoints of the chop line is removed.

   Select a location within the image window to begin your chop, press and
   hold any button. Next, move the pointer  to  another  location  in  the
   image.   As  you  move a line will connect the initial location and the
   pointer. When you release the button, the area within the image to chop
   is determined by which direction you choose from the Command widget.

   To  cancel  the  image  chopping, move the pointer back to the starting
   point of the line and release the button.

IMAGE ROTATION

   Press the / key to rotate the image 90  degrees  or  \  to  rotate  -90
   degrees.   To  interactively  choose  the  degree  of  rotation, choose
   Rotate...   of  the  Transform  submenu  from   the   Command   Widget.
   Alternatively, press * in the image window.

   A  small  horizontal  line is drawn next to the pointer. You are now in
   rotate mode. To exit immediately, press Dismiss. In  rotate  mode,  the
   Command widget has these options:

       Pixel Color

       black
       blue
       cyan
       green
       gray
       red
       magenta
       yellow
       white
       Browser...

       Direction

       horizontal
       vertical

       Help
       Dismiss

   Choose  a  background  color  from the Pixel Color sub-menu. Additional
   background colors can be specified with  the  color  browser.  You  can
   change the menu colors by setting the X resources pen1 through pen9.

   If  you  choose  the  color  browser and press Grab, you can select the
   background color by moving the pointer to  the  desired  color  on  the
   screen and press any button.

   Choose  a  point  in  the  image window and press this button and hold.
   Next, move the pointer to another location in the image. As you move  a
   line  connects  the  initial location and the pointer. When you release
   the button, the degree of image rotation is determined by the slope  of
   the  line  you  just  drew.  The slope is relative to the direction you
   choose from the Direction sub-menu of the Command widget.

   To cancel the image rotation, move the pointer  back  to  the  starting
   point of the line and release the button.

IMAGE ANNOTATION

   An  image is annotated interactively. There is no command line argument
   to annotate an image. To begin, choose Annotate of the Image Edit  sub-
   menu  from  the  Command  widget.  Alternatively,  press a in the image
   window.

   A small window appears showing the location of the cursor in the  image
   window.  You  are  now  in  annotate  mode.  To exit immediately, press
   Dismiss.  In annotate mode, the Command widget has these options:

   Font Name

   fixed

   variable

   5x8

   6x10

   7x13bold

   8x13bold

   9x15bold

   10x20

   12x24

   Browser...

   Font Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   transparent

   Browser...

   Box Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   transparent

   Browser...

   Rotate Text

   -90

   -45

   -30

   0

   30

   45

   90

   180

   Dialog...

   Help

   Dismiss

   Choose a font name from the Font Name sub-menu. Additional  font  names
   can  be  specified with the font browser. You can change the menu names
   by setting the X resources font1 through font9.

   Choose a font color from  the  Font  Color  sub-menu.  Additional  font
   colors can be specified with the color browser. You can change the menu
   colors by setting the X resources pen1 through pen9.

   If you select the color browser and press Grab, you can choose the font
   color  by  moving  the  pointer  to the desired color on the screen and
   press any button.

   If you choose to rotate the text, choose Rotate Text from the menu  and
   select  an  angle.  Typically  you will only want to rotate one line of
   text at a time. Depending on the angle you choose, subsequent lines may
   end up overwriting each other.

   Choosing  a  font  and its color is optional. The default font is fixed
   and the default color is black. However, you must choose a location  to
   begin  entering  text  and press a button. An underscore character will
   appear at the location of the pointer. The cursor changes to  a  pencil
   to indicate you are in text mode. To exit immediately, press Dismiss.

   In  text  mode,  any  key  presses  will  display  the character at the
   location of the underscore and advance  the  underscore  cursor.  Enter
   your  text  and  once  completed  press  Apply  to  finish  your  image
   annotation. To correct errors press BACK SPACE.  To  delete  an  entire
   line  of  text,  press DELETE.  Any text that exceeds the boundaries of
   the image window is automatically continued onto the next line.

   The actual color you request for  the  font  is  saved  in  the  image.
   However,  the color that appears in your Image window may be different.
   For example, on a monochrome screen the text will appear black or white
   even  if you choose the color red as the font color. However, the image
   saved to a file with -write is written with red  lettering.  To  assure
   the  correct  color  text  in the final image, any PseudoClass image is
   promoted to DirectClass (see miff(5)). To force a PseudoClass image  to
   remain PseudoClass, use -colors.

IMAGE COMPOSITING

   An  image  composite is created interactively. There is no command line
   argument to composite an image. To begin, choose Composite of the Image
   Edit  from  the  Command  widget.  Alternatively,  press x in the Image
   window.

   First a popup window is displayed requesting  you  to  enter  an  image
   name.   Press  Composite, Grab or type a file name. Press Cancel if you
   choose not to create a composite image. When you choose Grab, move  the
   pointer to the desired window and press any button.

   If  the  Composite  image  does not have any matte information, you are
   informed and the file browser is displayed again. Enter the name  of  a
   mask  image.  The image is typically grayscale and the same size as the
   composite image. If the image is not  grayscale,  it  is  converted  to
   grayscale and the resulting intensities are used as matte information.

   A  small window appears showing the location of the cursor in the image
   window. You are now in  composite  mode.  To  exit  immediately,  press
   Dismiss.  In composite mode, the Command widget has these options:

   Operators

   over

   in

   out

   atop

   xor

   plus

   minus

   add

   subtract

   difference

   bumpmap

   replace

   Blend

   Displace

   Help

   Dismiss

   Choose a composite operation from the Operators sub-menu of the Command
   widget. How each operator behaves is described below. image  window  is
   the  image  currently displayed on your X server and image is the image
   obtained

   over    The result is the union of the two  image  shapes,  with  image
          obscuring image window in the region of overlap.

   in       The  result  is simply image cut by the shape of image window.
          None of the image data of image window is in the result.

   out     The resulting image is image with the shape of image window cut
          out.

   atop     The  result  is  the  same  shape  as image window, with image
          obscuring image window where the image shapes overlap. Note this
          differs  from  over  because  the portion of image outside image
          window's shape does not appear in the result.

   xor     The result is the image data from both image and  image  window
          that is outside the overlap region. The overlap region is blank.

   plus    The result is just the sum of the image data. Output values are
          cropped to 255 (no overflow). This operation is  independent  of
          the matte channels.

   minus    The  result of image - image window, with underflow cropped to
          zero. The matte channel is ignored (set to 255, full coverage).

   add     The result of image +  image  window,  with  overflow  wrapping
          around (mod 256).

   subtract
            The  result  of  image - image window, with underflow wrapping
          around (mod 256). The add and subtract operators can be used  to
          perform reversible transformations.

   difference
            The  result  of  abs(image - image window). This is useful for
          comparing two very similar images.

   bumpmap
           The result of image window shaded by window.

   replace
           The resulting image is image window replaced with image.   Here
          the matte information is ignored.

          The  image  compositor requires a matte, or alpha channel in the
          image for some operations. This extra channel usually defines  a
          mask  which  represents a sort of a cookie-cutter for the image.
          This is the case when matte is 255 (full  coverage)  for  pixels
          inside  the shape, zero outside, and between zero and 255 on the
          boundary. If  image  does  not  have  a  matte  channel,  it  is
          initialized  with  0  for  any  pixel matching in color to pixel
          location (0,0), otherwise 255. See Matte Editing for a method of
          defining a matte channel.

          If  you  choose blend, the composite operator becomes over.  The
          image matte  channel  percent  transparency  is  initialized  to
          factor.   The image window is initialized to (100-factor). Where
          factor is the value you specify in the Dialog widget.

          Displace shifts the image pixels as defined  by  a  displacement
          map.   With  this  option,  image is used as a displacement map.
          Black, within  the  displacement  map,  is  a  maximum  positive
          displacement.  White  is  a  maximum  negative  displacement and
          middle gray is neutral. The displacement is scaled to  determine
          the  pixel  shift.  By default, the displacement applies in both
          the horizontal and vertical directions. However, if you  specify
          mask,  image  is  the  horizontal  X  displacement  and mask the
          vertical Y displacement.

          Note that matte information for image window is not retained for
          colormapped  X  server  visuals (e.g.  StaticColor, StaticColor,
          GrayScale,  PseudoColor).   Correct  compositing  behavior   may
          require   a  TrueColor  or  DirectColor  visual  or  a  Standard
          Colormap.

          Choosing a composite operator is optional. The default  operator
          is  replace.   However,  you must choose a location to composite
          your image and press button 1. Press and hold the button  before
          releasing  and  an  outline of the image will appear to help you
          identify your location.

          The actual colors of the composite image is saved. However,  the
          color  that  appears  in  image  window  may  be  different. For
          example, on a monochrome screen Image window will  appear  black
          or white even though your composited image may have many colors.
          If the image is saved to a file it is written with  the  correct
          colors.  To  assure  the  correct  colors are saved in the final
          image, any PseudoClass image is  promoted  to  DirectClass  (see
          miff).   To force a PseudoClass image to remain PseudoClass, use
          -colors.

COLOR EDITING

   Changing the the color of a set of pixels is  performed  interactively.
   There  is  no  command  line argument to edit a pixel. To begin, choose
   Color  from  the  Image   Edit   submenu   of   the   Command   widget.
   Alternatively, press c in the image window.

   A  small window appears showing the location of the cursor in the image
   window. You are now in color edit  mode.  To  exit  immediately,  press
   Dismiss.  In color edit mode, the Command widget has these options:

   Method

   point

   replace

   floodfill

   reset

   Pixel Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   Browser...

   Border Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   Browser...

   Fuzz

   0

   2

   4

   8

   16
       Dialog...

   Undo

   Help

   Dismiss

   Choose  a  color editing method from the Method sub-menu of the Command
   widget. The point method recolors any pixel selected with  the  pointer
   unless  the  button  is released. The replace method recolors any pixel
   that matches the color of the pixel you select  with  a  button  press.
   Floodfill  recolors  any  pixel that matches the color of the pixel you
   select with a button press and is  a  neighbor.   Whereas  filltoborder
   changes  the  matte  value of any neighbor pixel that is not the border
   color.  Finally reset changes the entire image to the designated color.

   Next, choose a pixel color from the Pixel  Color  sub-menu.  Additional
   pixel  colors  can  be specified with the color browser. You can change
   the menu colors by setting the X resources pen1 through pen9.

   Now press button 1 to select a pixel within the Image window to  change
   its  color.  Additional  pixels  may  be recolored as prescribed by the
   method you choose. additional pixels by increasing the Delta value.

   If the Magnify widget is mapped, it can be helpful in positioning  your
   pointer  within  the  image  (refer to button 2). Alternatively you can
   select a pixel to recolor from within  the  Magnify  widget.  Move  the
   pointer  to  the  Magnify widget and position the pixel with the cursor
   control keys. Finally, press a button to recolor the selected pixel (or
   pixels).

   The  actual  color  you  request  for the pixels is saved in the image.
   However, the color that appears in your Image window may be  different.
   For  example,  on  a  monochrome  screen the pixel will appear black or
   white even if you choose the color red as the pixel color. However, the
   image saved to a file with -write is written with red pixels. To assure
   the correct color text in the final image,  any  PseudoClass  image  is
   promoted  to  DirectClass  To  force  a  PseudoClass  image  to  remain
   PseudoClass, use -colors.

MATTE EDITING

   Matte information within an image is useful for some operations such as
   image  compositing.  This  extra  channel  usually defines a mask which
   represents a sort of a cookie-cutter for the image. This  is  the  case
   when  matte  is  255  (full coverage) for pixels inside the shape, zero
   outside, and between zero and 255 on the boundary.

   Setting the matte information in an image is done interactively.  There
   is no command line argument to edit a pixel. To begin, and choose Matte
   of the Image Edit sub-menu from the Command widget.

   Alternatively, press m in the image window.

   A small window appears showing the location of the cursor in the  image
   window.  You  are  now  in  matte edit mode. To exit immediately, press
   Dismiss.  In matte edit mode, the Command widget has these options:

   Method

   point

   replace

   floodfill

   reset

   Border Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   Browser...

   Fuzz

   0

   2

   4

   8

   16
       Dialog...

   Matte

   Undo

   Help

   Dismiss

   Choose a matte editing method from the Method sub-menu of  the  Command
   widget.  The  point  method  changes  the  matte value of the any pixel
   selected with the pointer until the button  is  released.  The  replace
   method  changes  the matte value of any pixel that matches the color of
   the pixel you select with a button press. Floodfill changes  the  matte
   value  of any pixel that matches the color of the pixel you select with
   a button press and is a neighbor.  Whereas  filltoborder  recolors  any
   neighbor  pixel that is not the border color. Finally reset changes the
   entire image to the designated matte value.  Choose Matte Value  and  a
   dialog  appears  requesting a matte value.  Enter a value between 0 and
   255. This value is assigned as the matte value of the selected pixel or
   pixels.   Now,  press  any  button  to  select a pixel within the Image
   window to change its matte value. You can change  the  matte  value  of
   additional  pixels  by  increasing  the Delta value. The Delta value is
   first added then subtracted from the red, green, and blue of the target
   color. Any pixels within the range also have their matte value updated.
   If the Magnify widget is mapped, it can be helpful in positioning  your
   pointer  within  the  image  (refer to button 2). Alternatively you can
   select a pixel to change  the  matte  value  from  within  the  Magnify
   widget.   Move the pointer to the Magnify widget and position the pixel
   with the cursor control keys. Finally, press a  button  to  change  the
   matte  value  of  the selected pixel (or pixels).  Matte information is
   only valid in a DirectClass image. Therefore, any PseudoClass image  is
   promoted to DirectClass. Note that matte information for PseudoClass is
   not retained  for  colormapped  X  server  visuals  (e.g.  StaticColor,
   StaticColor,  GrayScale,  PseudoColor) unless you immediately save your
   image to a file (refer to Write). Correct matte  editing  behavior  may
   require a TrueColor or DirectColor visual or a Standard Colormap.

IMAGE DRAWING

   An image is drawn upon interactively. There is no command line argument
   to draw on an image. To begin, choose Draw of the Image  Edit  sub-menu
   from the Command widget.  Alternatively, press d in the image window.

   The  cursor changes to a crosshair to indicate you are in draw mode. To
   exit immediately, press Dismiss. In draw mode, the Command  widget  has
   these options:

   Primitive

   point

   line

   rectangle

   fill rectangle

   circle

   fill circle

   ellipse

   fill ellipse

   polygon

   fill polygon

   Color

   black

   blue

   cyan

   green

   gray

   red

   magenta

   yellow

   white

   transparent

   Browser...

   Stipple

   Brick

   Diagonal

   Scales

   Vertical

   Wavy

   Translucent

   Opaque

   Open...

   Width

   1

   2

   4

   8

   16
       Dialog...

   Undo

   Help

   Dismiss

   Choose a drawing primitive from the Primitive sub-menu.

   Next,  choose a color from the Color sub-menu. Additional colors can be
   specified with the color browser. You can change  the  menu  colors  by
   setting  the  X  resources  pen1  through  pen9.  The transparent color
   updates the image matte channel and is useful for image compositing.

   If you choose the color browser and press  Grab,  you  can  select  the
   primitive  color  by  moving  the  pointer  to the desired color on the
   screen and press any button. The transparent color  updates  the  image
   matte channel and is useful for image compositing.

   Choose a stipple, if appropriate, from the Stipple sub-menu. Additional
   stipples can be specified with the file browser. Stipples obtained from
   the file browser must be on disk in the X11 bitmap format.

   Choose a line width, if appropriate, from the Width sub-menu. To choose
   a specific width select the Dialog widget.

   Choose a point in the image window and press button 1 and  hold.  Next,
   move  the pointer to another location in the image. As you move, a line
   connects the initial location and the pointer.  When  you  release  the
   button,  the  image  is  updated  with the primitive you just drew. For
   polygons, the image is updated when you press and  release  the  button
   without moving the pointer.

   To cancel image drawing, move the pointer back to the starting point of
   the line and release the button.

REGION OF INTEREST

   To begin, press choose Region of Interest of the Pixel  Transform  sub-
   menu  from  the  Command  widget.   Alternatively, press R in the image
   window.

   A small window appears showing the location of the cursor in the  image
   window.  You  are now in region of interest mode. In region of interest
   mode, the Command widget has these options:

   Help

   Dismiss

   To define a region of interest, press button 1 and drag. The region  of
   interest  is  defined  by  a  highlighted  rectangle  that  expands  or
   contracts as it follows the pointer. Once you are  satisfied  with  the
   region  of  interest, release the button. You are now in apply mode. In
   apply mode the Command widget has these options:

   File

   Save...

   Print...

   Edit

   Undo

   Redo

   Transform

   Flip

   Flop

   Rotate Right

   Rotate Left

   Enhance

   Hue...

   Saturation...

   Brightness...

   Gamma...

   Spiff

   Dull

   Equalize

   Normalize

   Negate

   GRAYscale

   Quantize...

   Effects

   Despeckle

   Emboss

   Reduce Noise

   Add Noise

   Sharpen...

   Blur...

   Threshold...

   Edge Detect...

   Spread...

   Shade...

   Raise...

   Segment...

   F/X

   Solarize...

   Swirl...

   Implode...

   Wave...

   Oil Paint

   Charcoal Draw...

   Miscellany

   Image Info

   Zoom Image

   Show Preview...

   Show Histogram

   Show Matte

   Help

   Dismiss

   You can make adjustments to  the  region  of  interest  by  moving  the
   pointer  to  one  of  the  rectangle  corners,  pressing  a button, and
   dragging. Finally,  choose  an  image  processing  technique  from  the
   Command widget. You can choose more than one image processing technique
   to apply to an area. Alternatively, you can move the region of interest
   before  applying  another  image  processing  technique. To exit, press
   Dismiss.

IMAGE PANNING

   When an image exceeds the width or  height  of  the  X  server  screen,
   display  maps  a  small  panning icon. The rectangle within the panning
   icon shows the area that  is  currently  displayed  in  the  the  image
   window.  To  pan about the image, press any button and drag the pointer
   within the panning icon.  The pan rectangle moves with the pointer  and
   the  image  window  is updated to reflect the location of the rectangle
   within the panning icon. When you have selected the area of  the  image
   you wish to view, release the button.

   Use  the arrow keys to pan the image one pixel up, down, left, or right
   within the image window.

   The panning icon is withdrawn if the image  becomes  smaller  than  the
   dimensions of the X server screen.

USER PREFERENCES

   Preferences  affect the default behavior of display(1). The preferences
   are either true or false and are  stored  in  your  home  directory  as
   .displayrc:

            display image centered on a backdrop"

                This  backdrop covers the entire workstation screen and is
                useful for hiding other X window  activity  while  viewing
                the  image.  The color of the backdrop is specified as the
                background color. Refer to X Resources for details.
            confirm on program exit"

                Ask for  a  confirmation  before  exiting  the  display(1)
                program.
            correct image for display gamma"

                If  the image has a known gamma, the gamma is corrected to
                match  that  of  the  X  server  (see   the   X   Resource
                displayGamma).
            display warning messages"

                Display any warning messages.
            apply Floyd/Steinberg error diffusion to image"

                The  basic  strategy  of  dithering  is to trade intensity
                resolution  for  spatial  resolution  by   averaging   the
                intensities  of  several neighboring pixels.  Images which
                suffer from severe contouring when reducing colors can  be
                improved with this preference.
            use a shared colormap for colormapped X visuals"

                This  option only applies when the default X server visual
                is PseudoColor or GRAYScale. Refer  to  -visual  for  more
                details.  By  default, a shared colormap is allocated. The
                image shares colors with  other  X  clients.   Some  image
                colors  could  be  approximated,  therefore your image may
                look very different than  intended.  Otherwise  the  image
                colors  appear exactly as they are defined. However, other
                clients may go technicolor  when  the  image  colormap  is
                installed.
            display images as an X server pixmap"

                Images  are  maintained  as  a XImage by default. Set this
                resource to True to utilize a server Pixmap instead.  This
                option  is  useful if your image exceeds the dimensions of
                your server screen  and  you  intend  to  pan  the  image.
                Panning  is  much  faster with Pixmaps than with a XImage.
                Pixmaps are considered a precious resource, use them  with
                discretion.

   GM IDENTIFY

          Identify describes the format and characteristics of one or more
          image files as internally supported by  the  software.  It  will
          also   report  if  an  image  is  incomplete  or  corrupt.   The
          information displayed includes the scene number, the file  name,
          the  width  and  height  of  the  image,  whether  the  image is
          colormapped or not, the number  of  colors  in  the  image,  the
          number  of  bytes  in  the image, the format of the image (JPEG,
          PNM, etc.), and finally the number of seconds in both user  time
          and  elapsed  time  it  took  to read and process the image.  If
          -verbose or +ping are provided as an option, the pixel read rate
          is also displayed. An example line output from identify follows:

              images/aquarium.miff 640x480 PseudoClass 256c
                     308135b MIFF 0.000u 0:01

          If -verbose is set, expect additional output including any image
          comment:

              Image: images/aquarium.miff
              class: PseudoClass
              colors: 256
              signature: eb5dca81dd93ae7e6ffae99a527eb5dca8...
              matte: False
              geometry: 640x480
                 depth: 8
              bytes: 308135
              format: MIFF
              comments:
              Imported from MTV raster image: aquarium.mtv

          For some formats, additional format-specific  information  about
          the  file  will  be  written  if  the -debug coder or -debug all
          option is used.

IDENTIFY OPTIONS

   Options are processed in command line order. Any option you specify  on
   the  command  line  remains in effect for the set of images immediately
   following, until the set is terminated by the appearance of any  option
   or -noop.

   For a more detailed description of each option, see Options, above.

   -authenticate <string>
          decrypt image with this password

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -format <string>
          output formatted image characteristics

   -help  print usage instructions

   -interlace <type>
          the type of interlacing scheme

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -log <string>
          Specify format for debug log

   -ping  efficiently determine image characteristics

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -size <width>x<height>{+offset}
          width and height of the image

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

          For a more detailed description of  each  option,  see  Options,
          above.

GM IMPORT

   Import  reads  an  image  from  any  visible  window on an X server and
   outputs it as an image file. You  can  capture  a  single  window,  the
   entire  screen,  or any rectangular portion of the screen.  Use display
   for  redisplay,  printing,  editing,   formatting,   archiving,   image
   processing, etc. of the captured image.

   The  target  window can be specified by id, name, or may be selected by
   clicking the mouse in the desired window. If you  press  a  button  and
   then  drag,  a  rectangle  will form which expands and contracts as the
   mouse moves.  To  save  the  portion  of  the  screen  defined  by  the
   rectangle,  just  release the button. The keyboard bell is rung once at
   the beginning of the screen capture and twice when it completes.

EXAMPLES

   To select an X window or an area of the screen with the mouse and  save
   it in the MIFF image format to a file entitled window.miff, use:

       gm import window.miff

   To  select an X window or an area of the screen with the mouse and save
   it  in  the  Encapsulated  PostScript  format  to  include  in  another
   document, use:

       gm import figure.eps

   To  capture  the  entire  X server screen in the JPEG image format in a
   file entitled root.jpeg, without using the mouse, use:

       gm import -window root root.jpeg

   To capture the 512x256 area at the upper right corner of the  X  server
   screen  in  the  PNG  image  format  in a well-compressed file entitled
   corner.png, without using the mouse,  use:

       gm import -window root -crop 512x256-0+0 -quality 90
              corner.png

OPTIONS

   Options are processed in command line order. Any option you specify  on
   the  command  line  remains in effect until it is explicitly changed by
   specifying the option again with a different effect.

   Import options can appear on the command line or in  your  X  resources
   file.  See X(1). Options on the command line supersede values specified
   in your X resources file.

   For a more detailed description of each option, see Options, above.

   -bordercolor <color>
          the border color

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -delay <1/100ths of a second>
          display the next image after pausing

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -descend
          obtain image by descending window hierarchy

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -encoding <type>
          specify the text encoding

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -frame include the X window frame in the imported image

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -help  print usage instructions

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -limit <type> <value>
          Disk, File,  Map,  Memory,  Pixels,  Width,  Height  or  Threads
          resource limit

   -log <string>
          Specify format for debug log

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -negate
          replace every pixel with its complementary color

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   -pause <seconds>
          pause between snapshots [import]

   -ping  efficiently determine image characteristics

   -pointsize <value>
          pointsize of the PostScript, X11, or TrueType font

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

   -rotate <degrees>{<}{>}
          rotate the image

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scene <value>
          set scene number

   -screen
          specify the screen to capture

   -set <attribute> <value>
          set an image attribute

   +set <attribute>
          unset an image attribute

   -silent
          operate silently

   -snaps <value>
          number of screen snapshots

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

   -transparent <color>
          make this color transparent within the image

   -trim  trim an image

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

          For  a  more  detailed  description of each option, see Options,
          above.

GM MOGRIFY

   Mogrify transforms an image or a sequence of images.  These  transforms
   include  image  scaling,  image  rotation, color reduction, and others.
   Each transmogrified image overwrites the corresponding original  image,
   unless  an  option  such  as  -format  causes the output filename to be
   different from the input filename.

   The   graphics   formats   supported   by   mogrify   are   listed   in
   GraphicsMagick(1).

EXAMPLES

   To convert all the TIFF files in a particular directory to JPEG, use:

       gm mogrify -format jpeg *.tiff

   To convert a directory full of JPEG images to thumbnails, use:

       gm mogrify -size 120x120 *.jpg -resize 120x120 +profile "*"

   In  this example, '-size 120x120' gives a hint to the JPEG decoder that
   the images are going to be downscaled to 120x120, allowing  it  to  run
   faster  by  avoiding returning full-resolution images to GraphicsMagick
   for the subsequent resizing operation.  The ´-resize 120x120' specifies
   the  desired dimensions of the output images.  It will be scaled so its
   largest dimension is 120 pixels.  The ´+profile "*"' removes  any  ICM,
   EXIF,  IPTC,  or  other profiles that might be present in the input and
   aren't needed in the thumbnails.

   To scale an image of a cockatoo to exactly 640 pixels in width and  480
   pixels in height, use:

       gm mogrify -resize 640x480! cockatoo.miff

OPTIONS

   Options  are processed in command line order. Any option you specify on
   the command line remains in effect for the set of images that  follows,
   until the set is terminated by the appearance of any option or -noop.

   For a more detailed description of each option, see Options, above.

   -affine <matrix>
          drawing transform matrix

   -antialias
          remove pixel aliasing

    -asc-cdl <spec>
          apply ASC CDL color transform

   -authenticate <string>
          decrypt image with this password

   -auto-orient
          orient (rotate) image so it is upright

   -background <color>
          the background color

   -black-threshold red[,green][,blue][,opacity]
          pixels below the threshold become black

   -blue-primary <x>,<y>
          blue chromaticity primary point

   -blur <radius>{x<sigma>}
          blur the image with a Gaussian operator

   -border <width>x<height>
          surround the image with a border of color

   -bordercolor <color>
          the border color

   -channel <type>
          the type of channel

   -charcoal <factor>
          simulate a charcoal drawing

   -colorize <value>
          colorize the image with the pen color

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -compose <operator>
          the type of image composition

   -compress <type>
          the type of image compression

   -contrast
          enhance or reduce the image contrast

   -convolve <kernel>
          convolve image with the specified convolution kernel

   -create-directories
          create output directory if required

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -cycle <amount>
          displace image colormap by amount

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -delay <1/100ths of a second>
          display the next image after pausing

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -despeckle
          reduce the speckles within an image

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -draw <string>
          annotate an image with one or more graphic primitives

   -edge <radius>
          detect edges within an image

   -emboss <radius>
          emboss an image

   -encoding <type>
          specify the text encoding

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -enhance
          apply a digital filter to enhance a noisy image

   -equalize
          perform histogram equalization to the image

   -extent <width>x<height>{+-}<x>{+-}<y>
          composite image on background color canvas image

   -fill <color>
          color to use when filling a graphic primitive

   -filter <type>
          use this type of filter when resizing an image

   -flip  create a "mirror image"

   -flop  create a "mirror image"

   -font <name>
          use this font when annotating the image with text

   -format <type>
          the image format type

   -frame <width>x<height>+<outer bevel width>+<inner bevel width>
          surround the image with an ornamental border

   -fuzz <distance>{%}
          colors within this Euclidean distance are considered equal

   -gamma <value>
          level of gamma correction

   -gaussian <radius>{x<sigma>}
          blur the image with a Gaussian operator

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -gravity <type>
          direction primitive  gravitates to when annotating the image.

   -green-primary <x>,<y>
          green chromaticity primary point

   -hald-clut <clut>
          apply a Hald CLUT to the image

   -help  print usage instructions

   -implode <factor>
          implode image pixels about the center

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -lat <width>x<height>{+-}<offset>{%}
          perform local adaptive thresholding

   -level <black_point>{,<gamma>}{,<white_point>}{%}
          adjust the level of image contrast

   -limit <type> <value>
          Disk,  File,  Map,  Memory,  Pixels,  Width,  Height  or Threads
          resource limit

   -linewidth
          the line width for subsequent draw operations

   -list <type>
          the type of list

   -log <string>
          Specify format for debug log

   -loop <iterations>
          add Netscape loop extension to your GIF animation

   -magnify
          magnify the image

   -map <filename>
          choose a particular set of colors from this image

   -mask <filename>
          Specify a clipping mask

   -matte store matte channel if the image has one

   -mattecolor <color>
          specify the color to be used with the -frame option

   -median <radius>
          apply a median filter to the image

   -minify <factor>
          minify the image

   -modulate brightness[,saturation[,hue]]
          vary the brightness, saturation, and hue of an image

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -motion-blur <radius>{x<sigma>}{+angle}
          Simulate motion blur

   -negate
          replace every pixel with its complementary color

   -noise <radius|type>
          add or reduce noise in an image

   -noop  NOOP (no option)

   -normalize
          transform image to span the full range of color values

   -opaque <color>
          change this color to the pen color within the image

   -operator channel operator rvalue[%]
          apply a mathematical, bitwise, or value  operator  to  an  image
          channel

   -ordered-dither <channeltype> <NxN>
          ordered dither the image

   -output-directory <directory>
          output files to directory

   -orient <orientation>
          Set the image orientation attribute

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   -paint <radius>
          simulate an oil painting

   -pen <color>
          (This option has been replaced by the -fill option)

   -pointsize <value>
          pointsize of the PostScript, X11, or TrueType font

   -profile <filename>
          add ICM, IPTC, or generic profile  to image

   -preserve-timestamp
          preserve the original timestamps of the file

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -raise <width>x<height>
          lighten or darken image edges

   -random-threshold <channeltype> <LOWxHIGH>
          random threshold the image

   -recolor <matrix>
          apply a color translation matrix to image channels

   -red-primary <x>,<y>
          red chromaticity primary point

   -region <width>x<height>{+-}<x>{+-}<y>
          apply options to a portion of the image

   -render
          render vector operations

   -repage  <width>x<height>+xoff+yoff[!]
          Adjust image page offsets

   -resample <horizontal>x<vertical>
          Resample image to specified horizontal and vertical resolution

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

   -roll {+-}<x>{+-}<y>
          roll an image vertically or horizontally

   -rotate <degrees>{<}{>}
          rotate the image

   -sample <geometry>
          scale image using pixel sampling

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scale <geometry>
          scale the image.

   -scene <value>
          set scene number

   -set <attribute> <value>
          set an image attribute

   +set <attribute>
          unset an image attribute

   -segment <cluster threshold>x<smoothing threshold>
          segment an image

   -shade <azimuth>x<elevation>
          shade the image using a distant light source

   -sharpen <radius>{x<sigma>}
          sharpen the image

   -shave <width>x<height>{%}
          shave pixels from the image edges

   -shear <x degrees>x<y degrees>
          shear the image along the X or Y axis

   -size <width>x<height>{+offset}
          width and height of the image

   -solarize <factor>
          negate all pixels above the threshold level

   -spread <amount>
          displace image pixels by a random amount

   -strip remove all profiles and text attributes from the image

   -stroke <color>
          color to use when stroking a graphic primitive

   -strokewidth <value>
          set the stroke width

   -swirl <degrees>
          swirl image pixels about the center

   -texture <filename>
          name of texture to tile onto the image background

   -threshold <value>{%}
          threshold the image

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

   -tile <filename>
          tile image when filling a graphic primitive

   -transform
          transform the image

   -transparent <color>
          make this color transparent within the image

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -units <type>
          the units of image resolution

   -unsharp <radius>{x<sigma>}{+<amount>}{+<threshold>}
          sharpen the image with an unsharp mask operator

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -view <string>
          FlashPix viewing parameters

   -virtual-pixel <method>
          specify contents of "virtual pixels"

   -wave <amplitude>x<wavelength>
          alter an image along a sine wave

   -white-point <x>,<y>
          chromaticity white point

   -white-threshold red[,green][,blue][,opacity]
          pixels above the threshold become white

          For  a  more  detailed  description of each option, see Options,
          above.

GM MONTAGE

   montage creates a composite image by combining several separate images.
   The  images are tiled on the composite image with the name of the image
   optionally appearing just below the individual tile.

   The composite image is constructed in the following manner. First, each
   image  specified on the command line, except for the last, is scaled to
   fit the maximum tile size. The maximum tile size by default is 120x120.
   It  can  be  modified  with  the  -geometry  command line argument or X
   resource. See Options for more information on command  line  arguments.
   See  X(1)  for  more information on X resources.  Note that the maximum
   tile size need not be a square.

   Next the composite image is initialized with the color specified by the
   -background  command  line argument or X resource. The width and height
   of the composite image  is  determined  by  the  title  specified,  the
   maximum  tile  size, the number of tiles per row, the tile border width
   and height, the image border width, and the label height. The number of
   tiles  per  row  specifies how many images are to appear in each row of
   the composite image. The default is to have 5 tiles in each row  and  4
   tiles  in  each column of the composite.  A specific value is specified
   with -tile. The tile border width and  height,  and  the  image  border
   width  defaults  to the value of the X resource -borderwidth. It can be
   changed with the -borderwidth or -geometry command line argument  or  X
   resource.  The  label height is determined by the font you specify with
   the -font command line argument or X resource. If you do not specify  a
   font,  a  font  is  chosen that allows the name of the image to fit the
   maximum width of a tiled area.  The label colors is determined  by  the
   -background  and  -fill command line argument or X resource. Note, that
   if the background and pen colors are the same, labels will not appear.

   Initially, the composite image title is placed at the  top  if  one  is
   specified  (refer to -fill). Next, each image is set onto the composite
   image, surrounded by its border color,  with  its  name  centered  just
   below  it. The individual images are left-justified within the width of
   the tiled area.  The order of the images is the same as they appear  on
   the  command  line  unless  the images have a scene keyword. If a scene
   number is specified in each image, then the images are tiled  onto  the
   composite  in  the  order  of  their  scene  number.  Finally, the last
   argument on the command line is the  name  assigned  to  the  composite
   image.  By  default, the image is written in the MIFF format and can be
   viewed or printed with display(1).

   Note, that if the number of tiles exceeds the default number of  20  (5
   per  row,  4  per column), more than one composite image is created. To
   ensure a single image is produced, use -tile to increase the number  of
   tiles to meet or exceed the number of input images.

   Finally,  to  create one or more empty spaces in the sequence of tiles,
   use the "NULL:" image format.

   Note, a composite MIFF image displayed to  an  X  server  with  display
   behaves  differently  than other images. You can think of the composite
   as a visual image directory. Choose a particular tile of the  composite
   and press a button to display it. See display(1) and miff(5)

EXAMPLES

   To  create  a  montage  of  a cockatoo, a parrot, and a hummingbird and
   write it to a file called birds, use:

       gm montage cockatoo.miff parrot.miff hummingbird.miff
               birds.miff

   To tile several bird images so that they are  at  most  256  pixels  in
   width  and  192  pixels  in  height,  surrounded  by  a red border, and
   separated by 10 pixels of background color, use:

       gm montage -geometry 256x192+10+10 -bordercolor red
               birds.* montage.miff

   To create an unlabeled parrot image, 640 by 480 pixels, and  surrounded
   by a border of black, use:

       gm montage -geometry 640x480 -bordercolor black
               -label "" parrot.miff bird.miff

   To create an image of an eagle with a textured background, use:

       gm montage -texture bumps.jpg eagle.jpg eagle.png

   To  join  several  GIF  images together without any extraneous graphics
   (e.g.  no label, no shadowing, no surrounding tile frame), use:

       gm montage +frame +shadow +label -tile 5x1
               -geometry 50x50+0+0 *.png joined.png

OPTIONS

   Any option you specify on the command line remains in  effect  for  the
   group  of  images  following  it,  until the group is terminated by the
   appearance of any option or -noop.  For example, to make a  montage  of
   three  images,  the  first with 32 colors, the second with an unlimited
   number of colors, and the third with only 16 colors, use:

       gm montage -colors 32 cockatoo.1 -noop cockatoo.2
                -colors 16 cockatoo.3 cockatoos.miff

   For a more detailed description of each option, see Options, above.

   -adjoin
          join images into a single multi-image file

   -affine <matrix>
          drawing transform matrix

   -authenticate <string>
          decrypt image with this password

   -background <color>
          the background color

   -blue-primary <x>,<y>
          blue chromaticity primary point

   -blur <radius>{x<sigma>}
          blur the image with a Gaussian operator

   -bordercolor <color>
          the border color

   -borderwidth <geometry>
          the border width

   -chop <width>x<height>{+-}<x>{+-}<y>{%}
          remove pixels from the interior of an image

   -colors <value>
          preferred number of colors in the image

   -colorspace <value>
          the type of colorspace

   -comment <string>
          annotate an image with a comment

   -compose <operator>
          the type of image composition

   -compress <type>
          the type of image compression

   -crop <width>x<height>{+-}<x>{+-}<y>{%}
          preferred size and location of the cropped image

   -debug <events>
          enable debug printout

   -define <key>{=<value>},...
          add coder/decoder specific options

   -density <width>x<height>
          horizontal and vertical resolution in pixels of the image

   -depth <value>
          depth of the image

   -display <host:display[.screen]>
          specifies the X server to contact

   -dispose <method>
          GIF disposal method

   -dither
          apply Floyd/Steinberg error diffusion to the image

   -draw <string>
          annotate an image with one or more graphic primitives

   -encoding <type>
          specify the text encoding

   -endian <type>
          specify endianness (MSB, LSB, or Native) of image

   -fill <color>
          color to use when filling a graphic primitive

   -filter <type>
          use this type of filter when resizing an image

   -font <name>
          use this font when annotating the image with text

   -frame <width>x<height>+<outer bevel width>+<inner bevel width>
          surround the image with an ornamental border

   -gamma <value>
          level of gamma correction

   -geometry <width>x<height>{+-}<x>{+-}<y>{%}{@}{!}{^}{<}{>}
          Specify dimension, offset, and resize options.

   -gravity <type>
          direction primitive  gravitates to when annotating the image.

   -green-primary <x>,<y>
          green chromaticity primary point

   -help  print usage instructions

   -interlace <type>
          the type of interlacing scheme

   -label <name>
          assign a label to an image

   -limit <type> <value>
          Disk, File,  Map,  Memory,  Pixels,  Width,  Height  or  Threads
          resource limit

   -log <string>
          Specify format for debug log

   -matte store matte channel if the image has one

   -mattecolor <color>
          specify the color to be used with the -frame option

   -mode <value>
          mode of operation

   -monitor
          show progress indication

   -monochrome
          transform the image to black and white

   -noop  NOOP (no option)

   -page <width>x<height>{+-}<x>{+-}<y>{%}{!}{<}{>}
          size and location of an image canvas

   -pen <color>
          (This option has been replaced by the -fill option)

   -pointsize <value>
          pointsize of the PostScript, X11, or TrueType font

   -quality <value>
          JPEG/MIFF/PNG/TIFF compression level

   -red-primary <x>,<y>
          red chromaticity primary point

   -render
          render vector operations

   -repage  <width>x<height>+xoff+yoff[!]
          Adjust image page offsets

   -resize <width>x<height>{%}{@}{!}{<}{>}
          resize an image

   -rotate <degrees>{<}{>}
          rotate the image

   -sampling-factor <horizontal_factor>x<vertical_factor>
          chroma subsampling factors

   -scenes <value-value>
          range of image scene numbers to read

   -shadow <radius>{x<sigma>}
          shadow the montage

   -sharpen <radius>{x<sigma>}
          sharpen the image

   -size <width>x<height>{+offset}
          width and height of the image

   -strip remove all profiles and text attributes from the image

   -stroke <color>
          color to use when stroking a graphic primitive

   -strokewidth <value>
          set the stroke width

   -texture <filename>
          name of texture to tile onto the image background

   -thumbnail <width>x<height>{%}{@}{!}{<}{>}
          resize an image (quickly)

   -tile <geometry>
          layout of images [montage]

   -title <string>
          assign title to displayed image [animate, display, montage]

   -transform
          transform the image

   -transparent <color>
          make this color transparent within the image

   -treedepth <value>
          tree depth for the color reduction algorithm

   -trim  trim an image

   -type <type>
          the image type

   -verbose
          print detailed information about the image

   -version
          print GraphicsMagick version string

   -white-point <x>,<y>
          chromaticity white point

          For  a  more  detailed  description of each option, see Options,
          above.

X RESOURCES

   Montage options can appear on the command line or in  your  X  resource
   file.  Options on the command line supersede values specified in your X
   resource file. See X(1) for more information on X resources.

   All montage options have  a  corresponding  X  resource.  In  addition,
   montage uses the following X resources:

   background (class Background)
          background color

          Specifies  the  preferred  color  to use for the composite image
          background.  The default is #ccc.

   borderColor (class BorderColor)
          border color

          Specifies the preferred color to use  for  the  composite  image
          border. The default is #ccc.

   borderWidth (class BorderWidth)
          border width

          Specifies the width in pixels of the composite image border. The
          default is 2.

   font (class Font)
          font to use

          Specifies the name of the preferred font to use when  displaying
          text  within the composite image. The default is 9x15, fixed, or
          5x8 determined by the composite image size.

   matteColor (class MatteColor)
          color of the frame

          Specify the color of an image frame. A 3D effect is achieved  by
          using  highlight  and shadow colors derived from this color. The
          default value is #697B8F.

   pen (class Pen)
          text color

          Specifies the  preferred  color  to  use  for  text  within  the
          composite image.  The default is black.

   title (class Title)
          composite image title

          This resource specifies the title to be placed at the top of the
          composite image. The default is not to place a title at the  top
          of the composite image.

GM TIME

DESCRIPTION

   time  executes  an  arbitrary  gm  utility  command  (e.g. convert) and
   reports the user and  elapsed  time.   This  provides  way  to  measure
   command  execution  times  similar  to the Unix ´time' command but in a
   portable and consistent way.

EXAMPLES

   To obtain time information for the execution of a command:

   % gm time convert input.ppm -gaussian 0x2 output.ppm convert  input.ppm
   -gaussian  0x2  output.ppm     22.60s user 0.00s system 2354% cpu 0.960
   total

   Here is the interpretation of the above output:

       user - the total user time consumed.
       system - the total system time consumed.
       total - the total elapsed time consumed.

OPTIONS

   The time command reqires no  options  other  than  the  gm  command  to
   execute.

GM VERSION

DESCRIPTION

   version  displays  the  software  release version, build quantum (pixel
   sample)  depth,  web  site  URL,  copyright  notice,  enabled  features
   support,  configuration  parameters,  and  final  build options used to
   build the software.  The  available  information  depends  on  how  the
   software was configured and the host system.

EXAMPLES

   To display the version information:

     % gm -version
     GraphicsMagick 1.3.19 2013-12-31 Q16 http://www.GraphicsMagick.org/
     Copyright (C) 2002-2013 GraphicsMagick Group.
     Additional copyrights and licenses apply to this software.
     See http://www.GraphicsMagick.org/www/Copyright.html for details.
     Feature Support:
       Thread Safe              yes
       Large Files (> 32 bit)   yes
       Large Memory (> 32 bit)  no
       BZIP                     yes
       DPS                      no
       FlashPix                 no
       FreeType                 yes
       Ghostscript (Library)    no
       JBIG                     no
       JPEG-2000                yes
       JPEG                     yes
       Little CMS               yes
       Loadable Modules         no
       OpenMP                   yes (201107)
       PNG                      yes
       TIFF                     yes
       TRIO                     no
       UMEM                     yes
       WMF                      no
       X11                      yes
       XML                      yes
       ZLIB                     yes
     Host type: i386-pc-solaris2.11
     Configured using the command:
       ./configure  ...
     Final Build Parameters:
       CC       = ...
       CFLAGS   = ...
       CPPFLAGS = ...
       CXX      = ...
       CXXFLAGS = ...
       LDFLAGS  = ...
       LIBS     = ...

OPTIONS

   The version command does not currently support any options.





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