recordaifc(1)                                                    recordaifc(1)


NAME
     sfrecord, recordaifc, recordaiff - record an audio file


SYNOPSIS
     sfrecord [sfoptions] [options] filename
     recordaifc [options] filename
     recordaiff [options] filename
     sfoptions:     [-w samplewidth]
     options:  [-help] [-verbose]
               [-n nchannels]
               [-s samplefmt]
               [-r rate]
               [-t time secs]
               [-f filefmt]
               [-d device]
               [-c compression]

DESCRIPTION
     sfrecord creates an output file containing audio sample data recorded
     through the audio hardware.  sfrecord records audio input for a time
     equal to a given -t argument, or until the user sends it an interrupt.
     The file's sampling rate will be equal to the rate of the default audio
     input device.  This can be set via the -r argument.  The format,
     compression, and channel count can be set via the appropriate arguments.

     Silicon Graphics has adopted AIFF-C (".aifc" suffix) as its standard
     interchange file format for digital audio sample data.  AIFF-C is an
     extension of the AIFF standard which includes support for compressed
     audio data.  The recordaifc and recordaiff programs provide a restricted
     interface to sfrecord as follows:

     recordaifc creates output files exclusively in AIFF-C (or AIFF) file
     format, and supports a smaller number of compression types.  recordaiff
     creates output files in AIFF file format with no compression options.

     The -c option allows you to compress audio data in real-time while
     writing it to an formats which support compression. There are several
     compression algorithms available: G.711 2:1 mu-law or A-law recommended
     for 8 KHz, 16-bit mono or multichannel data, G.722 4:1 compression
     recommended for 16 KHz, 16-bit mono or stereo data, G726, G728, GSM,
     MPEG1 Audio, and DVI ADPCM (for WAVE files only).

     When any of these programs receives a user interrupt, it writes all
     sample data in the audio buffer out to disk and updates the header before
     it exits.

     recordaiff and recordaifc are installed as links to sfrecord for backward
     compatibility. The only difference between the first two is that
     recordaifc creates AIFF-C files by default, while recordaiff creates AIFF
     files by default.  sfrecord's functionality is a superset of the others.


OPTIONS
     -h   help: print out a list of command line options and their
          descriptions

     -v   verbose: output to stdout

     -f   file format: aifc or aiff [for recordaifc], aifc, aiff, next, wave,
          or raw [for sfrecord].

     -n   number of channels: 1 = mono, 2 = stereo, 4 = 4-channel,

     -s   sample format: 8, 16 [for recordaifc]

     -d   audio device from which to get audio

     -r   sample rate: 48000, 44100, 32000, etc

     -c   compression type (mono or stereo AIFF-C only): ulaw , alaw, or g722

     -t   length of recording session in seconds: floating point value

FILES
     Source code for recordaifc is installed here:
     /usr/share/src/dmedia/soundcommands

BUGS
     To record files containing sample data which is compressed with G.722 or
     Aware you will need to run recordaifc with nondegrading high priority
     (this is especially true for stereo compressed data).

     If being run as root, the priority is set to NDPNORMMAX which is the
     highest normal process priority.  If run as a user, the process is set to
     the highest non-degrading priority allowed by the system.  This parameter
     is unfortunately by default lower than any normal process, but can be
     changed using systune(1M).  Alternately, see the man page npri(1) for
     information about how to set custom priorities and time slices.


SEE ALSO
     playaifc(1), apanel(1), aiff2aifc(1), aifcresample(1), aifccompress(1)


                                                                        Page 2