[mediacapture-record] Input video track width and height MUST be recorded and playable (#173)

guest271314 has just created a new issue for https://github.com/w3c/mediacapture-record:

== Input video track width and height MUST be recorded and playable ==
> The UA MUST record MediaRecorder/stream in such a way that the original
>  video Track(s) width and height can be retrieved at playback time. The {{Blob}}
>  containing entire recording returned when the recording finishes or smaller 
>  buffers of data returned at regular intervals containing the combination of all 
>  the original video Track(s) width and height MUST playback the input video Track(s) 
>  width and height.

The specification does not currently clearly state that input video track(s) width and height MUST be recorded and reflected in the `Blob` or smaller buffers of data recorded by `MediaRecorder`.

Currently at Chromium 76  neither variable video track input `width` and `height` are NOT output at the resulting `Blob` either by using `canvas.captureStream()`, `HTMLMediaElement.captureStream()` or `WebRTC` https://bugs.chromium.org/p/chromium/issues/detail?id=972470.

It is reasonable for users of `MediaRecorder` to expect variable width and height input to be reflected in the resulting media file(s).

This change fixes the omission in the specification as to what MUST occur as to recording and outputting a media file which contains variable witdth and and height input and makes it clear that the width and height of each input video track (image) MUST be recorded and output at both single `Blob` and multiple `Blobs` at `dataavailable` event.

Pull Request https://github.com/w3c/mediacapture-record/pull/172

Please view or discuss this issue at https://github.com/w3c/mediacapture-record/issues/173 using your GitHub account

Received on Sunday, 23 June 2019 01:28:17 UTC