1200768 - WebrtcVideoConduit cannot cope with having more than one H264 recv codec

Status: RESOLVED FIXED

(Core :: WebRTC: Audio/Video, defect, P3)

Description

[Byron Campen [:bwc]]

Currently, we can only have one H264 recv codec on a given WebrtcVideoConduit. If there are multiple H264 codecs in an answer, the last one will be what is configured, which is of course not likely to be what is sent. This will need to be fixed before we are able to accept multiple codecs in an answer.

There are a handful of possible fixes, including:

1. Only use the first H264 recv codec (will probably squeak by in most cases, since the other end will probably not actually switch on us).
2. Fix this limitation by having multiple H264 decoders.
3. Only offer one H264 codec in the first place.

Comment 1

[Byron Campen [:bwc]]

What do you think about these options? I have option 1 implemented in my simulcast negotiation work, and it works ok. If this is not enough in the short-term, I'll need to modify the simulcast patch to not put multiple different codecs (per simulcast version) in answers, and only use one recv codec like before.

Comment 2

[Maire Reavy [:mreavy]]

Let's land option 1, and file a followup for option 2 at a lower priority.  

Byron - are you good with this?  Thanks.

Comment 3

[Byron Campen [:bwc]]

We've already landed option 1 in bug 1203246. We can leave this bug for option 2.

Comment 4

[Bulk Bug Changes for mreavy's org]

Mass change P2->P3 to align with new Mozilla triage process.

Comment 6

[Andreas Pehrson [:pehrsons]]

Here's a manual repro case: https://jsfiddle.net/pehrsons/h1x8ytj9/

Comment 7

[Andreas Pehrson [:pehrsons]]

Attachment: Bug 1200768 - Forward all receive codec payload types to libwebrtc. r?jib!, r?ng!

Comment 8

[BugBot [:suhaib / :marco/ :calixte]]

The severity field for this bug is set to S3. However, the following bug duplicate has higher severity:

• Bug 1950834: S2

:pehrsons, could you consider increasing the severity of this bug to S2?

For more information, please visit BugBot documentation.

Comment 9

[Andreas Pehrson [:pehrsons]]

Not S2, this has been around forever.

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/41b771516141
Forward all receive codec payload types to libwebrtc. r=ng,jib

Comment 11

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/51159 for changes under testing/web-platform/tests

Comment 12

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/41b771516141

Comment 13

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR merged by moz-wptsync-bot