Timing Metadata

[aboba]

How is timing information carried across the pipeline (between VideoFrames and encodedChunks, serialization/deserialization on the wire, between encodedChunks and VideoFrames)?

Timing Model discussed at November VI

VideoFrameCallbackMetaData in rVFC specification includes receiveTime, captureTime, rtpTimestamp, mediaTime.

Resolution: “file specific issues on specific specs”

Related: Issue 601: Expose in VideoFrame
Related: w3c/mediacapture-transform#88

Use case: https://www.w3.org/TR/webrtc-nv-use-cases/#auction

[fippo]

Proposal: add timing metadata to RTCEncoded*Metadata

• receiveTime as defined in rVFC
• captureTime (#137, #159, defined in rVFC)

[alvestrand]

the question with timing data is always "in which clock?" And in particular, with cross-network flows, "how can you tell how fast/slow/offset the other end's clock is?"