[Linphone-developers] Implementing sound support for non-standard hardware

[Daniel Kabs [ML]]

Hello Linphone-Developers,

running Linux on an ARM platform, I managed to compile libosip-0.9.7
and linphone-0.12.2 "out of the box". I compiled the command line
version "linphonec" using ¹)

./configure --prefix=/usr --enable-gnome-ui=no

Problem:
My kernel is version 2.2 and has neither OSS nor ALSA support and uses
non-standard devices to play and record sound. These devices work with
8kHz, mono PCM data (either 8 bit A-Law or 12 bit linear). I'd like to
make linphone work with my audio hardware.

My first idea was to define a new soundcard type in
mediastreamer::sndcard.c that "interfaces" to my hardware's audio
devices.

Can you give me any hints about what functionality is required by the
interface functions defined in mediastreamer::sndcard.h::SndCard ?

Do you know if these functions will change in linphone-1.x ?

If so, I'd be better off writing an OSS/ALSA driver. Although in my
opinion, writing an OSS or ALSA driver is not the best idea, as it
probably takes a lot of time or may not even be possible for my audio
hardware (due to its limited capabilities) and for my "old" kernel.


Thanks for your help,
Cheers
Daniel Kabs
Germany



¹) Configure did not abort because I have a "faked" sys/soundcard.h
include file.
The resulting config.log showed:
ac_cv_header_machine_soundcard_h=no
ac_cv_header_soundcard_h=no
ac_cv_header_sys_soundcard_h=yes
ac_cv_header_sys_audio_h=no