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[me-media-timed-events] Merged Pull Request: Rewrite gap analysis and recommendations for sync

From: Chris Needham via GitHub <sysbot+gh@w3.org>
Date: Fri, 22 Feb 2019 14:49:24 +0000
To: public-web-and-tv@w3.org
Message-ID: <pull_request.closed-254660512-1550846963-sysbot+gh@w3.org>
chrisn has just merged tidoust's pull request 38 for https://github.com/w3c/me-media-timed-events:

== Rewrite gap analysis and recommendations for sync ==
This is an attempt to improve sections on synchronization. It is meant to take into account:
- discussions on frame accuracy in https://github.com/w3c/media-and-entertainment/issues/4
- discussions in the [last Media Timed Events Task Force call](https://lists.w3.org/Archives/Public/public-web-and-tv/2019Feb/0040.html). I kept the first recommendation on synchronization intact though. I don't really see how to rewrite it in the end (the recommendations that the document makes are not prescriptions, they are wishes, which match the notion of target goal that we talked about on Monday)
- [Nigel's comment on "sync to next frame"](https://lists.w3.org/Archives/Public/public-web-and-tv/2019Feb/0041.html)

In practice, the rewrite re-shuffles and completes the text that talked about synchronization to:
- bring together mechanisms that web apps can use as subsections within the same "synchronized rendering of web resources", without distinguishing between text track cues and other non media web content
- clarify the synchronization challenge, notably due to rendering of media content following a different path and clock
- list specific needs in generic terms, not linked to the notion of cues
- distinguish between progress along the media timeline and detection of a frame boundary (needed in some cases but not all)
- add a recommendation for a mechanism that would allow to detect frame boundaries when that is needed.

The update also adds more terms to the terminology section.

I note the text would still benefit from an example of use case that requires synchronization at an higher rate than the video frame rate, as described in issue #36.


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<a href="https://pr-preview.s3.amazonaws.com/tidoust/me-media-timed-events/pull/38.html" title="Last updated on Feb 22, 2019, 2:45 PM UTC (4fa63e3)">Preview</a> | <a href="https://pr-preview.s3.amazonaws.com/w3c/me-media-timed-events/38/3149624...tidoust:4fa63e3.html" title="Last updated on Feb 22, 2019, 2:45 PM UTC (4fa63e3)">Diff</a>

See https://github.com/w3c/me-media-timed-events/pull/38
Received on Friday, 22 February 2019 14:49:26 UTC

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