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r.composite(1grass)


NAME

   r.composite   -  Combines red, green and blue raster maps into a single
   composite raster map.

KEYWORDS

   raster, composite, RGB

SYNOPSIS

   r.composite
   r.composite --help
   r.composite  [-dc]  red=name  green=name  blue=name    [levels=integer]
   [level_red=integer]      [level_green=integer]     [level_blue=integer]
   output=name  [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
   -d
       Dither

   -c
       Use closest color

   --overwrite
       Allow output files to overwrite existing files

   --help
       Print usage summary

   --verbose
       Verbose module output

   --quiet
       Quiet module output

   --ui
       Force launching GUI dialog

   Parameters:
   red=name [required]
       Name of raster map to be used for <red>

   green=name [required]
       Name of raster map to be used for <green>

   blue=name [required]
       Name of raster map to be used for <blue>

   levels=integer
       Number of levels to be used for each component
       Options: 1-256
       Default: 32

   level_red=integer
       Number of levels to be used for <red>
       Options: 1-256

   level_green=integer
       Number of levels to be used for <green>
       Options: 1-256

   level_blue=integer
       Number of levels to be used for <blue>
       Options: 1-256

   output=name [required]
       Name for output raster map

DESCRIPTION

   This program combines three raster maps to form a  composite  RGB  map.
   For  each  input  map layer, the corresponding component from the map's
   color table is used (e.g. for the red map, the red component  is  used,
   and so on). In general, the maps should use a grey-scale color table.

NOTES

   The  default  number  of  intensity  levels  for  each component is 32,
   resulting in a total of 32768 possible colors (equivalent  to  15  bits
   per  pixel).  If significantly more levels than this are used, not only
   will r.composite take longer to run, but displaying the resulting layer
   with d.rast will also be significantly slower.

   Floyd-Steinberg dithering is optionally used with the -d flag.

EXAMPLES

   RGB composite of three satellite bands
   Color composite of a LANDSAT scene (North Carolina sample dataset):
   g.region raster=lsat7_2002_10
   r.composite blue=lsat7_2002_10 green=lsat7_2002_20 red=lsat7_2002_30 \
               output=lsat7_2002_rgb

   RGB composite with dithering
   Creating  a  composite RGB raster using 32 color levels per layer, with
   dithering:
   r.composite -d red=elevation.r green=elevation.g blue=elevation.b \
               output=elev.composite

SEE ALSO

    d.rast, d.rgb, r.blend, r.colors, r.rgb

    Wikipedia Entry: Floyd-Steinberg dithering

AUTHOR

   Glynn Clements

   Last changed: $Date: 2014-12-28 16:42:58 +0100 (Sun, 28 Dec 2014) $

SOURCE CODE

   Available at: r.composite source code (history)

   Main index | Raster index | Topics index | Keywords index  |  Graphical
   index | Full index

    2003-2016 GRASS Development Team, GRASS GIS 7.2.0 Reference Manual



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