Bug 275829 – setCodecPreferences should accept or video codecs regardless of mimeType case

• Component: WebRTC
• Status: RESOLVED DUPLICATE

[Ahmad Saleem]

Hi Team,

While investigating WPT failures, I noticed that Safari / WebKit (including Chrome due to relying on libwebrtc) fails following:

Test Case: https://wpt.fyi/results/webrtc/RTCRtpTransceiver-setCodecPreferences.html?label=master&label=experimental&aligned&q=Safari%3Afail

This assert following error: "InvalidModificationError: RTCRtpCodecCapability bad mimeType"

Which stems from: https://searchfox.org/wubkat/rev/38fb2ecadd89df8d6d7114cc2b030188d744aeb0/Source/WebCore/Modules/mediastream/libwebrtc/LibWebRTCRtpTransceiverBackend.cpp#92

webrtc::RtpCodecCapability rtcCodec;
    if (codec.mimeType.startsWith("video/"_s))
        rtcCodec.kind = cricket::MEDIA_TYPE_VIDEO;
    else if (codec.mimeType.startsWith("audio/"_s))
        rtcCodec.kind = cricket::MEDIA_TYPE_AUDIO;
    else
        return Exception { ExceptionCode::InvalidModificationError, "RTCRtpCodecCapability bad mimeType"_s };

So this might need tweaking.

Web-Spec: https://w3c.github.io/webrtc-pc/#dom-rtcrtptransceiver-setcodecpreferences

While spec says in Step 7:

For each codec in codecs,

If codec does not match any codec in codecCapabilities, throw InvalidModificationError.

_____

So if I am not mistaken Chrome and Safari are doing right thing while Firefox / Gecko is wrong here.

Just wanted to get input before suggesting that we should update WPT or not.

Thanks!

[Radar WebKit Bug Importer]

<rdar://problem/130928226>

[Ahmad Saleem]

Gecko is right here - https://github.com/w3c/webrtc-pc/pull/2975

Thanks Youenn for input. :-)

[Ahmad Saleem]

I fixed it will find relevant commit and link, never realized, I filed this.

[Ahmad Saleem]

*** This bug has been marked as a duplicate of bug 307157 ***