tree 8f9aef40a4a0a5345e0f903cae309d0e6e3fcea9
parent ec967d74f7111600419d244e6a7351d1ff531896
author Philipp Maier <pmaier@sysmocom.de> 1679500410 +0100
committer Philipp Maier <pmaier@sysmocom.de> 1679915570 +0200

mgcp_codec: fix oa/bwe comparison in mgcp_codec_pt_translate()

The function mgcp_codec_pt_translate is very strict when comparing the
codecs to each other to find a matching payload type number to be used
on the egress side.

This poses a problem when one side uses AMR in bandwith-efficient, while
the other side uses AMR in octet-aligned payload type format. To the pt
translate function the difference in the payload format will appear as
if the codec were different and eventually the payload type number
cannot be translated.

since osmo-mgw offers conversion between the payload type format it
would be no problem to ignore the payload type format when making the
translation decision. The only exception here would be if one side would
announce AMR two times, the first time with octet-aligned and the second
time with bandwith-efficient format. Then we would have to use the
payload type number from the exact match. (and skip any formatconversion)

To archive such an optimized decision we will first go through the codec
lists and perform an exact match. If we don't get a match we go through
the codec lists a second time, but this time we ignore the payload
format.

Change-Id: Ifbd201a2749009a4644a29bd77e1d0fc0c124a9d
Related: OS#5461