convert(1)
NAME
convert − convert an audio file
SYNOPSIS
/opt/audio/bin/convert [source_file target_file -sfmt format -dfmt format -ddata data_type -srate rate -drate rate -schannels number -dchannels number]
DESCRIPTION
This command converts audio files from one supported file format, data format, sampling rate, and number of channels to another. The unconverted file is retained as a source file.
-sfmt format -dfmt format
are the file formats for the source and destination files. Each format can be one of these:
au Sun file format
snd NeXT file format
wav Microsoft RIFF Waveform file format
u MuLaw format
al ALaw
l16 linear 16-bit format
lo8 offset (unsigned) linear 8-bit format
l8 linear 8-bit format
If you omit -sfmt, convert uses the header or filename extension in the source file. You can omit -dfmt if you supply a filename extension for the destination file.
-ddata data_type
is the data type for the destination files. data_type can be one of these:
u MuLaw
al ALaw
l16 linear 16-bit
lo8 offset (unsigned) linear 8-bit data
l8 linear 8-bit data
If you omit -ddata, convert uses an appropriate data type, normally the data type of the source file.
-srate rate -drate rate
are the number of samples per second for the source and destination file. Typical sampling rates range from 8 to 11k (for voice quality) to 44,100 (for CD quality). You can use k to indicate thousands. For example, 8k means 8,000 samples per second.
If you omit -srate, convert uses a rate defined by the source file header or its filename extension. For a raw file with no extension, 8,000 is used. By playing the file, you can determine if 8,000 samples is too fast or too slow.
If you omit -drate, convert uses a sampling rate appropriate for the destination file format; if possible, it matches the sampling rate of the source file.
-schannels number -dchannels number
are the number of channels in the source and destination files. Use 1 for mono; 2 for stereo. If -schannels is omitted, convert uses the information in the header; for raw data files, it uses mono.
If -dchannels is omitted, convert matches what was used for the source file (through the header or -schannels option); for raw data files, it uses mono.
EXAMPLES
Convert a raw data file to a headered file.
cd /opt/audio/bin
convert beep.l16 beep.au
Convert a raw data file to a headered file when the source has no extension, was sampled at 11,025 per second, and has stereo data.
cd /opt/audio/bin
convert beep beep.au -sfmt l16 -srate 11025 -schannels 2
To save disk space, convert an audio file with CD quality sound to voice quality sound.
cd /opt/audio/bin
convert idea.au idea2.au -ddata u -drate 8k -dchannels 1
AUTHOR
convert was developed by HP. Sun is a trademark of Sun MicroSystems, Inc.
NeXT is a trademark of NeXT Computers, Inc.
Microsoft is a trademark of Microsoft Corporation.
SEE ALSO
audio(5), asecure(1m), aserver(1m), attributes(1), send_sound(1).
Using the Audio Developer’s Kit
Hewlett-Packard Company — HP-UX Release 10.20: July 1996