arecord(1)


NAME

   arecord,  aplay  -  command-line  sound  recorder  and  player for ALSA
   soundcard driver

SYNOPSIS

   arecord [flags] [filename]
   aplay [flags] [filename [filename]] ...

DESCRIPTION

   arecord is a command-line soundfile recorder  for  the  ALSA  soundcard
   driver.  It  supports several file formats and multiple soundcards with
   multiple devices. If recording with interleaved mode samples  the  file
   is automatically split before the 2GB filesize.

   aplay  is  much  the  same,  only  it  plays  instead of recording. For
   supported soundfile formats, the sampling rate, bit depth, and so forth
   can be automatically determined from the soundfile header.

   If filename is not specified, the standard output or input is used. The
   aplay utility accepts multiple filenames.

OPTIONS

   -h, --help
          Help: show syntax.

   --version
          Print current version.

   -l, --list-devices
          List all soundcards and digital audio devices

   -L, --list-pcms
          List all PCMs defined

   -D, --device=NAME
          Select PCM by name

   -q --quiet
          Quiet mode. Suppress messages (not sound :))

   -t, --file-type TYPE
          File type (voc, wav, raw or au).  If this parameter  is  omitted
          the WAVE format is used.

   -c, --channels=#
          The  number  of  channels.   The  default is one channel.  Valid
          values are 1 through 32.

   -f --format=FORMAT
          Sample format
          Recognized sample formats are: S8 U8 S16_LE S16_BE U16_LE U16_BE
          S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE
          FLOAT_BE      FLOAT64_LE      FLOAT64_BE      IEC958_SUBFRAME_LE
          IEC958_SUBFRAME_BE  MU_LAW  A_LAW  IMA_ADPCM  MPEG  GSM  SPECIAL
          S24_3LE S24_3BE U24_3LE U24_3BE S20_3LE S20_3BE U20_3LE  U20_3BE
          S18_3LE S18_3BE U18_3LE
          Some of these may not be available on selected hardware
          The available format shortcuts are:
          -f cd (16 bit little endian, 44100, stereo) [-f S16_LE -c2 -r44100]
          -f cdr (16 bit big endian, 44100, stereo) [-f S16_BE -c2 -f44100]
          -f dat (16 bit little endian, 48000, stereo) [-f S16_LE -c2 -r48000]
          If no format is given U8 is used.

   -r, --rate=#<Hz>
          Sampling  rate in Hertz. The default rate is 8000 Hertz.  If the
          value specified is less than 300, it is taken  as  the  rate  in
          kilohertz.  Valid values are 2000 through 192000 Hertz.

   -d, --duration=#
          Interrupt after # seconds.  A value of zero means infinity.  The
          default is zero, so if this option is omitted then  the  arecord
          process will run until it is killed.

   -s, --sleep-min=#
          Min ticks to sleep. The default is not to sleep.

   -M, --mmap
          Use memory-mapped (mmap) I/O mode for the audio stream.  If this
          option is not set, the read/write I/O mode will be used.

   -N, --nonblock
          Open the audio device in non-blocking mode.  If  the  device  is
          busy  the  program will exit immediately.  If this option is not
          set the program will block until the audio device  is  available
          again.

   -F, --period-time=#
          Distance  between  interrupts  is  # microseconds.  If no period
          time and no period size is given then a quarter  of  the  buffer
          time is set.

   -B, --buffer-time=#
          Buffer  duration  is  #  microseconds  If  no buffer time and no
          buffer size is given then the maximal allowed  buffer  time  but
          not more than 500ms is set.

   --period-size=#
          Distance between interrupts is # frames If no period size and no
          period time is given then a quarter of the buffer size is set.

   --buffer-size=#
          Buffer duration is # frames If no buffer time and no buffer size
          is  given then the maximal allowed buffer time but not more than
          500ms is set.

   -A, --avail-min=#
          Min available space for wakeup is # microseconds

   -R, --start-delay=#
          Delay for automatic PCM start is  #  microseconds  (relative  to
          buffer size if <= 0)

   -T, --stop-delay=#
          Delay for automatic PCM stop is # microseconds from xrun

   -v, --verbose
          Show PCM structure and setup.  This option is accumulative.  The
          VU meter is displayed when this is given twice or three times.

   -V, --vumeter=TYPE
          Specifies the VU-meter type, either stereo or mono.  The  stereo
          VU-meter  is  available  only  for 2-channel stereo samples with
          interleaved format.

   -I, --separate-channels
          One file for each channel.  This option  disables  max-file-time
          and  use-strftime,  and ignores SIGUSR1.  The stereo VU meter is
          not available with separate channels.

   -P     Playback.  This is the default if  the  program  is  invoked  by
          typing aplay.

   -C     Record.  This is the default if the program is invoked by typing
          arecord.

   -i, --interactive
          Allow  interactive  operation   via   stdin.    Currently   only
          pause/resume via space or enter key is implemented.

   -m, --chmap=ch1,ch2,...
          Give  the  channel  map  to  override  or  follow.  Pass channel
          position strings like FL, FR, etc.

          If a device supports the override  of  the  channel  map,  aplay
          tries  to pass the given channel map.  If it doesn't support the
          channel map override but  still  it  provides  the  channel  map
          information,  aplay  tries to rearrange the channel order in the
          buffer to match with the returned channel map from the device.

   --disable-resample
          Disable automatic rate resample.

   --disable-channels
          Disable automatic channel conversions.

   --disable-format
          Disable automatic format conversions.

   --disable-softvol
          Disable software volume control (softvol).

   --test-position
          Test ring buffer position.

   --test-coef=<coef>
          Test  coefficient  for  ring  buffer  position;  default  is  8.
          Expression for validation is: coef * (buffer_size / 2).  Minimum
          value is 1.

   --test-nowait
          Do not wait for the ring buffer ‐ eats the whole CPU.

   --max-file-time
          While recording, when the  output  file  has  been  accumulating
          sound  for  this  long,  close  it  and  open a new output file.
          Default is the maximum size supported by the file format: 2  GiB
          for    WAV    files.     This    option   has   no   effect   if
          --separate-channels is specified.

   --process-id-file <file name>
          aplay writes its process ID here, so  other  programs  can  send
          signals to it.

   --use-strftime
          When  recording,  interpret  %-codes  in the file name parameter
          using the strftime facility whenever the output file is  opened.
          The  important  strftime codes are: %Y is the year, %m month, %d
          day of the  month,  %H  hour,  %M  minute  and  %S  second.   In
          addition,  %v  is  the  file  number,  starting at 1.  When this
          option is specified, intermediate  directories  for  the  output
          file  are  created  automatically.  This option has no effect if
          --separate-channels is specified.

   --dump-hw-params
          Dump hw_params of the device preconfigured status to stderr. The
          dump lists capabilities of the selected device such as supported
          formats, sampling rates, numbers of channels, period and  buffer
          bytes/sizes/times.   For  raw  device hw:X this option basically
          lists hardware capabilities of the soundcard.

   --fatal-errors
          Disables  recovery  attempts  when  errors   (e.g.   xrun)   are
          encountered; the aplay process instead aborts immediately.

SIGNALS

   When  recording, SIGINT, SIGTERM and SIGABRT will close the output file
   and exit.  SIGUSR1 will close the output file,  open  a  new  one,  and
   continue    recording.    However,   SIGUSR1   does   not   work   with
   --separate-channels.

EXAMPLES

   aplay -c 1 -t raw -r 22050 -f mu_law foobar
          will play the raw file "foobar"  as  a  22050-Hz,  mono,  8-bit,
          Mu-Law .au file.

   arecord -d 10 -f cd -t wav -D copy foobar.wav
          will  record  foobar.wav  as  a 10-second, CD-quality wave file,
          using the PCM "copy" (which  might  be  defined  in  the  user's
          .asoundrc file as:
          pcm.copy {
            type plug
            slave {
              pcm hw
            }
            route_policy copy
          }

   arecord -t wav --max-file-time 30 mon.wav
          Record  from the default audio source in monaural, 8,000 samples
          per second, 8 bits per  sample.   Start  a  new  file  every  30
          seconds.  File names are mon-nn.wav, where nn increases from 01.
          The file after mon-99.wav is mon-100.wav.

   arecord   -f   cd   -t   wav   --max-file-time   3600    --use-strftime
   %Y/%m/%d/listen-%H-%M-%v.wav
          Record  in  stereo  from the default audio source.  Create a new
          file every hour.  The files are placed in directories  based  on
          their start dates and have names which include their start times
          and file numbers.

SEE ALSO

    alsamixer(1), amixer(1)

BUGS

   Note that .aiff files are not currently supported.

AUTHOR

   arecord and aplay are by Jaroslav Kysela <perex@perex.cz> This document
   is by Paul Winkler <zarmzarm@erols.com>.  Updated for Alsa 0.9 by James
   Tappin <james@xena.uklinux.net>

                            1 January 2010                        APLAY(1)





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