G.729 and G.723.1 codecs for Asterisk open source PBX
Asterisk 1.4, 1.6, 1.8, 10.0 - 17.0 are supported.
To compile the codecs it is recommended to install Intel IPP libraries for better performance. Alternatively, download and install Bcg729 - a slightly slower implementation written in portable C99. Only G.729 will be available in that case.
The codecs are tested against Bcg729 1.0.2, IPP 5.3 - 8.2. Users of IPP 9.0 and IPP 2017 must also install IPP Legacy libraries. AMD processors works with IPP too.
To install legacy IPP libraries:
tar xf ipp90legacy_lin_9.0.0.008.tar cd ipp90legacy_lin/ unzip linux.zip ... password: accept mv linux /opt/intel/ipp/legacy
legacy/ in the root of IPP installation directory (under
Additionally, static libraries from the Intel compiler are required:
cd /opt/intel/ipp/legacy/lib wget http://asterisk.hosting.lv/bin/icc-static-libs.tar.bz2 tar xjf icc-static-libs.tar.bz2
./autogen.sh to generate GNU Autoconf files, then
./configure. Check available options with
./configure --help. Specify
--prefix in case Asterisk is installed in non-standard location.
G.723.1 send rate is configured in Asterisk codecs.conf file:
[g723] ; 6.3kbps stream, default sendrate=63 ; 5.3kbps ;sendrate=53
This option is for outgoing voice stream only. It does not affect incoming stream that should be decoded automatically whatever the bit-rate is.
There are also two Asterisk CLI commands
g723 debug and
g729 debug to print statistics about received frames sizes. This can aid in debugging audio problems. Bump Asterisk verbosity level to 3 to see the numbers.
astconv is audio format conversion utility similar to Asterisk
file convert command. Build it with supplied
build-astconv.sh script against Asterisk 1.8 or later. astconv loads codec_*.so modules directly to perform the conversion. Use codec module that was compiled against same Asterisk version the astconv was built against.
The translation result could be used to: (a) confirm the codec is working properly; (b) prepare voice-mail prompts, for example:
./astconv ./codec_g729.so -e 160 file.slin file.g729 ./astconv ./codec_g729.so -d 10 file.g729 file.slin ./astconv ./codec_g723.so -e 480 file.slin file.g723 ./astconv ./codec_g723.so -d 24 file.g723 file.slin
file.slin is signed linear 16-bin 8kHz mono audio, you can play it with alsa-utils:
aplay -f S16_LE file.slin
and convert between other formats with SOX:
sox input.wav -e signed-integer -b 16 -c 1 -r 8k -t raw output.slin sox -t raw -e signed-integer -b 16 -c 1 -r 8k input.slin output.wav
- codec_g72x.c, astconv.c, build-astconv.sh - GPLv3;
- autoconf files initially contributed by Michael.Kromer at computergmbh dot de;
- g723_slin_ex.h, g729_slin_ex.h, slin_g72x_ex.h - sample speech data;
- ipp/ files are a copy from IPP samples, IPP license apply.