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Must support `a=rtcp-fb:*` when checking RTP capabilities

Open ibc opened this issue 2 years ago • 0 comments

(Same as in mediasoup-client: https://github.com/versatica/mediasoup-client/issues/239).

a=rtcp-fb:* means that all codecs in this m= section support the RTCP features exposed in this attribute line. Purpose of it is to save space in the SDP by reducing number of a=rtcp-fb lines per m= section. libwebrtc will support this soon so we must be ready in mediasoup-client and libmediasoupclient.

Example: a=rtcp-fb:* transport-cc means that all codecs in this m= section support transport-cc.

NOTE: This is a SDP thing. We transmit ORTC parameters from client to mediasoup and vice-versa. AFAIU we don't need to support this neither in mediasoup side nor in the ORTC parameters, utils and definitions within mediasoup-client and libmediasoupclient.

So basically, when we parse a SDP and generate RtpParameters or RtpCapabilities must be ready to manage a=rtcp-fb:* lines and apply their supported RTCP features into all codecs within the generated RtpParameters or RtpCapabilities. This is just an estimation, things may need to be different.

ibc avatar Jan 18 '23 09:01 ibc