[pjsip] pjsua on Raspberry Pi (SEKCobra - John) - answer by Silvio

[SL]

Hi John,
Raspberry doesn't have a direct audio input for microphone and dealing 
with stereo audio output through o/s layer can lead you to trouble in 
getting good audio.
I have solved this problem from scratch by designing an hardware audio 
codec and its user space driver that works directly with PjMedia audio 
packets, through SPI interface.
Aimed to build a video-doorphone, I build my board with all hardware 
needed for it.
You can have a look to my video-doorphone pet-project in my English site:
http://www.lugato.co.uk
The development board you can see surfing my site is full functional and 
tested: it has all the hardware needed to easily build an "hassle free" 
IP video-doorphone system based on Raspberry PI (both internal and 
external stations).
It is currently assembled by an Italian firm for internal development of 
IP video-doorphone hardware.
If you are interested to have a sample of this board, feel free to 
contact me through the contact form you can find in my site.
Please note that it is currently based on Rasbpian Wheezy and Pjproject 
2.3, since PjMedia running on Raspbian Jessie isn't able to recognize 
Raspicam and I had no time to spend in finding the reason of this 
problem, since it was actually not needed: Raspicam works perfectly with 
PjMedia running on Rasbpian Wheezy... but I would be curious to know the 
reason why Raspicam doesn't work with PjMedia+Jessie.
Please take also in account that H264 video compression works fine only 
on Raspberry PI 2 and 3, since the old Raspberry board doesn't have 
enough computational power for it, but old Raspberry can manage H263+ 
video compression quite well. I recommend using PI3 ;)
If you just need audio, you can install Rasbpian Jessie with the last 
version of Pjproject on Raspberry PI connected to this board.
Have fun!
Silvio

> Message: 1
> Date: Tue, 22 Nov 2016 23:23:59 +0100
> From: SEKCobra <sekcobra at gmail.com>
> To: pjsip at lists.pjsip.org
> Subject: [pjsip] pjsua on Raspberry Pi
> Message-ID: <7cd7f109-9928-cd8d-fd4f-222b80940332 at gmail.com>
> Content-Type: text/plain; charset="utf-8"; Format="flowed"
>
> Hey people,
>
> I hope I'm in the right place bothering all of you, but I need some help
> with getting a little project going. Background:
> I'm trying to connect my apartments door intercom to a USB soundcard and
> then be able to connect to it when someone rings the door.
>
> I've hit a somewhat significant issue tho: I was able to compile
> pjproject 2.1.0 without a hiccup, but there are several issues
> interfacing with the soundcard.
>
> First of all, there's zero audio. You can tell there is a change in
> status when pjsua is started because of slight noise setting in, but
> in-call there's nothing but silence, the call being ended because of
> inactivity after a bit. Testing it with the onboard audio output, there
> actually is (Very quiet and bad) audio being transmitted.
>
> When a call is ended, I always get this and the program seems to hang
> somewhat:
> 23:16:10.115    pjsua_aud.c  .Closing USB Audio Device: USB Audio
> (hw:1,0) sound playback device and USB Audio Device: USB Audio (hw:1,0)
> sound capture device
>
> I can play wav's fine through aplay. pjsystest's "Play Tone" also works,
> with the hang I described above occuring. When I use the "Device Test" I
> get the following:
>
> 1
> 23:22:54.598      systest.c  Running Audio Device Test
> Expression 'SetApproximateSampleRate( pcm, hwParams, sr )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1294
> Expression 'PaAlsaStreamComponent_InitialConfigure( &self->capture,
> inParams, self->primeBuffers, hwParamsCapture, &realSr )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1870
> Expression 'PaAlsaStream_Configure( stream, inputParameters,
> outputParameters, sampleRate, framesPerBuffer, &inputLatency,
> &outputLatency, &hostBufferSizeMode )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1994
> Expression 'SetApproximateSampleRate( pcm, hwParams, sr )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1294
> Expression 'PaAlsaStreamComponent_InitialConfigure( &self->capture,
> inParams, self->primeBuffers, hwParamsCapture, &realSr )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1870
> Expression 'PaAlsaStream_Configure( stream, inputParameters,
> outputParameters, sampleRate, framesPerBuffer, &inputLatency,
> &outputLatency, &hostBufferSizeMode )' failed in
> 'src/../../../portaudio/src/hostapi/alsa/pa_linux_alsa.c', line: 1994
> Unable to open device: Invalid sample rate (err=469996)
> Error
> Sorry we encountered error with the testInvalid sample rate
>
> If anyone can help me out here, I'd really appreciate it greatly!
>
> Best regards,
> John