[Linphone-developers] Stereo Payload Types

[Nicholas J Humfrey]

Hi,

I am looking at using oRTP for strereo payload types (specifically  
static payload number 10). I have been looking at the oRTP API and  
working out how best to implement it.

Option 1: Add a 'int channels;' to the PayloadType structure. But  
this might cause problems with binary compatibility?

Option 2: Use one of the private oRTP flags (eg PAYLOAD_TYPE_PRIV1)  
to indicate that the payload is stereo.


Ideally I would like to be able to do:

pt = rtp_profile_find_payload_number(&avprofile, "L16", 44100, 2);

and

pt = rtp_profile_get_payload_number_from_rtpmap(&avprofile,  
"L16/44100/2");


Would be nice to get payloads 10 and 11 added to oRTP's default list  
of static payload types...

nick.




static char null_bytes[] = {0x00, 0x00, 0x00, 0x00};

PayloadType payload_type_l16_mono=
{
        PAYLOAD_AUDIO_CONTINUOUS, // type
        44100,          // clock rate
        16,                     // bits per frame
        null_bytes,     // zero pattern
        2,                      // pattern_length
        705600,         // normal_bitrate (44100 x 16bits per frame x 1 channel)
        "L16",                // MIME Type
        1,                      // Channels
};


PayloadType payload_type_l16_stereo=
{
        PAYLOAD_AUDIO_CONTINUOUS, // type
        44100,          // clock rate
        32,                     // bits per frame
        null_bytes,     // zero pattern
        4,                      // pattern_length
        1411200,        // normal_bitrate (44100 x 16bits per frame x 2 
channels)
        "L16",                // MIME Type
        2,                      // Channels
};