54 lines
2.8 KiB
Groff
54 lines
2.8 KiB
Groff
.TH GENTONES 1
|
||
.SH NAME
|
||
gentones \- generates tones
|
||
.SH SYNOPSIS
|
||
gentone wave2alaw <wav file> <alaw file>
|
||
.br
|
||
gentone wave2ulaw <wav file> <ulaw file>
|
||
.br
|
||
gentone tone2alaw <frq1> <frq2> <length> <fade in> <fade out> <alaw file>
|
||
.br
|
||
gentone tone2ulaw <frq1> <frq2> <length> <fade in> <fade out> <ulaw file>
|
||
.SH DESCRIPTION
|
||
Length and fade lengths must be given in samples (8000 samples are one second).
|
||
Tones will append to existing files, wav files don't.
|
||
Frequencies may be given as floating point values.
|
||
.br
|
||
It can be used, to generate law encoded tones with one or two frequencies.
|
||
This is mainly used to create patterns, like dial tones, busy tone and other audio
|
||
patterns. Depending on your telephone system, you need to use "tones2alaw" or "tones2ulaw".
|
||
There are two frequencies to specify "frq1" and "frq2". If only one frequency should be
|
||
used, enter 0 for "frq2". The "length" specifies the total length of the tone in samples. 8000
|
||
samples are one second. 2000 samples are 1/4 of a second. "fade in" and "fade out" is used to
|
||
make the start and stop of the tone soft. If "fade in" is 800, the sound will fade in
|
||
within 1/10 of a second.
|
||
This makes tones very smooth and avoids the ‘click’ sound at the beginning.
|
||
"fade out" respectively. Whatever specified for "fade in" and "fade out", the tone will
|
||
be as long as given at "length". If you don’t want to use fades, set "frq1" and "frq2" to
|
||
"0". I suggest at least 50 sample for fade to silence.
|
||
.br
|
||
The given file will be appended to "alaw file" or "ulaw file". If you like
|
||
to create a new one, but the name still exist, delete the file and then start creating it. This
|
||
is useful to create a sample with more than one tone. Example: A busy tone normally is made out of
|
||
1/2 second of a tone, and one 1/2 second of silence. To add silence, just enter 0 for "frq1"
|
||
and "frq2".
|
||
.br
|
||
It is also possible to convert a wave file to a-law or mu-law. The wave file
|
||
must have a sampling rate of 8000. It doesn’t matte what bit-resolution or how many
|
||
channels it has (stereo or mono). The sampling rate will not be converted, so it must be
|
||
8000 samples/second. The resolution should be 16 bits for best quality. a-law and
|
||
mu-law have better resolution than 8 bits. The data of a-law and mu-law is 8 bits
|
||
sample, but since it is quantised, the quality will be 12 bits. 12 bits sounds almost as good as 16
|
||
bits. Wave files are only available with 8 or 16 bits resolution.
|
||
.br
|
||
The use of a-law or mu-law files, result in a faster processing, since the
|
||
samples must not be converted into a-law or mu-law for ISDN use. ISDN uses only a-law or mu-law
|
||
samples.
|
||
.SH SEE ALSO
|
||
http://www.linux-call-router.de/doc.html
|
||
.SH AUTHOR
|
||
This minimal man page was written by Victor Seva
|
||
<linuxmaniac@torreviejawireless.org>
|
||
.br
|
||
from documentation created by Andreas Eversberg <jolly@eversberg.eu>
|