- From: Bernard Aboba via GitHub <sysbot+gh@w3.org>
- Date: Thu, 21 Nov 2024 19:15:01 +0000
- To: public-webrtc-logs@w3.org
If we are clear about what constitutes the "media format" for each codec, and what the defaults are in the absence of fmtp parameters, we can avoid unnecessary negotiation failures. For example: For VP8 - max-fs and max-fr parameters are not part of the "media format", only mimeType - Browser advertising no parameters should be able to succesfully negotiate with browser including max-fs/max-fr For H264 - "media format" includes mimeType, profile-level-id (because profile and level-id are combined), packetization-mode, level-asymmetry-allowed - packetization-mode = 0 assumed if omitted? - With level-asymmetry-allowed in Offer & Answer, Offer of level-id A and Answer of level-id B will fail negotiation if B != A even if profile and packetization-mode matches. This is a design error in RFC 6184, so not clear we can fix it. For VP9 - "media format" includes mimeType, profile-id - profile-id = 0 assumed if omitted? - Browser advertising no parameters should be able to succesfully negotiate with browser including profile-id=0, max-fs/max-fr For AV1 - "media format" includes mimeType, profile, tier - profile=0, tier=0 assumed if omitted - level-idx=5 assumed if omitted - level-idx represents max level that can be sent (sendonly), received (receiveonly) - level-idx represents max level that can be sent/received (sendrecv) - Offer of level-idx 4 is observed to cause a negotiation failure if Answerer supports level-idx 5 -- GitHub Notification of comment by aboba Please view or discuss this issue at https://github.com/w3c/webrtc-pc/issues/3024#issuecomment-2492061065 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Thursday, 21 November 2024 19:15:02 UTC