[rtcweb] JSEPbis: setCodecPreferences and send/receive-only codecs
Bernard Aboba <bernard.aboba@gmail.com> Thu, 15 February 2024 15:34 UTC
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From: Bernard Aboba <bernard.aboba@gmail.com>
Date: Thu, 15 Feb 2024 07:33:54 -0800
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To: RTCWeb IETF <rtcweb@ietf.org>
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Subject: [rtcweb] JSEPbis: setCodecPreferences and send/receive-only codecs
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The W3C WEBRTC WG is currently dealing with Issues that have arisen with codecs that can only be sent or only received. As an example, there are browsers that can only receive H.265, but cannot send it (since they do not support encoding). Similarly, there are browsers that can send profiles of H.264 (and possibly H.265) that they cannot receive. The AVTCORE WG discussed the potential implications at the virtual interim meeting that occurred on February 13, 2024. Slides are here: https://docs.google.com/presentation/d/1gSOrVyB9jK32fynJUx2O-noJCvcTMQrvvFqlkFhfTV8/edit#slide=id.g268da8c9c26_0_145 Reviewing current implementations, it appears that there are some unexpected results and in many cases, that it is necessary to negotiate 2 m-lines, one for each direction. Discussion is currently ongoing in the following places: - AVTCORE: - WebRTC-HEVC Issue 22 <https://github.com/aboba/hevc-webrtc/issues/22> - W3C WEBRTC WG: - w3c/webrtc-pc#2936 <https://github.com/w3c/webrtc-pc/issues/2936> - w3c/webrtc-pc#2933 <https://github.com/w3c/webrtc-pc/issues/2933> - w3c/webrtc-pc#2935 <https://github.com/w3c/webrtc-pc/pull/2935> - w3c/webrtc-pc/#2888 <https://github.com/w3c/webrtc-pc/issues/2888>
- [rtcweb] JSEPbis: setCodecPreferences and send/re… Bernard Aboba