On Tuesday, December 11, 2012 12:04:59 PM Wurzer Juergen wrote: > Hi! > > Is there a way to deactivate the silence suppression during a phone call on > a GTA02 and/or on a GTA04? Maybe like setting the level of the voice > activity detection (VAD) to a minimum, so that it always stays "active" > and continuously transmit the voice. > > I need this because we have a research project where we embed > steganographic informations during a call into the voice stream. The > current problem is that if the audio signal is very quiet (e.g. the person > doesn't speak) nothing is transmitted because of the silence suppression - > this leads to the steganographic informations being discarded.
On GTA04 it's possible to do software voice routing - i think in this case the sounds will be under your control. If you want to test it, try make a call and then select "Speaker" from the context menu. The sound will be then routed by program /opt/qtmoko/bin/gsm-voice-routing - source code is here [1]. By default it uses speex echo cancellation, but these lines can be commented out or you can even replace the program with bash script that calls arecord and aplay - see here [2] > Maybe there are AT commands? > I have tried to set some AT commands like the ones shown at > http://wiki.openmoko.org/wiki/Manually_using_GSM on GTA02. You can stop QtMoko with /etc/init.d/qtmoko-gta04 stop and open and use the serial port e.g. with minicom. Regards Radek [1] https://github.com/radekp/gta04-gsm-voice-routing [2] http://projects.goldelico.com/p/gta04-kernel/page/Wireless/ _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community