Cellular Network Infrastructure » OsmoMGW

Probably I am overlooking/misunderstanding something here. Or this ticket is a duplicate of #3334. I am not sure.

From my understanding the client API has everything needed to negotiate multiple codec options. However, some parameters can not be altered, the sample rate (8000 in almost all cases) and the number of channels (always 1) can not be influenced. The ptime parameter (which is alsways 20 in our cases) can not be set individually for each codec. However I think it should, but SDP does not allow a per-codec ptime setting.

See: http://git.osmocom.org/osmo-mgw/tree/include/osmocom/mgcp_client/mgcp_client.h

In struct mgcp_msg

One findes two members:
enum mgcp_codecs codecs[MGCP_MAX_CODECS];
unsigned int codecs_len;

The member codecs can be populated with up to 10 codecs from enum mgcp_codecs. The payload types are automatically selected depending on IANA/3gpp recomendations. (If it is really necessary to map a codec to a different payload type one can do so by using the ptmap member.)

See also: https://osmocom.org/issues/3334