Bug 268987 – [Cocoa] WebCodecs H264 decoder is not always reordering frames according presentation time

• Component: Media
• Status: RESOLVED FIXED

[youenn fablet]

Follow up to https://bugs.webkit.org/show_bug.cgi?id=263901, it seems that not all video streams get reordered properly.

[Radar WebKit Bug Importer]

<rdar://problem/122544744>

[youenn fablet]

Full repro steps from Marcello:
- pull the code:
  - either from https://github.com/marcello3d/webcodecs/tree/marcello/frame-out-of-order-logging
  - apply the patch yourself to https://github.com/w3c/webcodecs https://patch-diff.githubusercontent.com/raw/w3c/webcodecs/pull/734.patch
- run the server with `node server` in the samples folder
- open http://localhost:8888/ in safari
- open developer console to see javascript logs
- leave settings at 2D & h264
- click start

[youenn fablet]

Our parsing of SPS is not liking samples/data/bbb_video_avc_frag.mp4

[Marcello Bastea-Forte]

I can find more test files, if that’s helpful. This is basically the last technical blocker to getting descript.com working on Safari/ipad/iphone.

[youenn fablet]

Pull request: https://github.com/WebKit/WebKit/pull/24076

[EWS]

Committed 274353@main (875db7cbec49): <https://commits.webkit.org/274353@main>

Reviewed commits have been landed. Closing PR #24076 and removing active labels.

[Marcello Bastea-Forte]

okay I just tested this on Safari Technology Preview 190 (Safari 17.4, WebKit 19619.1.5.5.2)

it's fixed on the h264 example, hurray! 

But the h265 example still fails :(

Error: Decoded frame 166666 µs out of order, last frame was 200000 µs

[Marcello Bastea-Forte]

filed the new bug as https://bugs.webkit.org/show_bug.cgi?id=270645