Bug 254417

Summary: [GStreamer] Dash video freezes after swapping between manifest variants
Product: WebKit Reporter: laurence.ejraee
Component: WPE WebKitAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: bugs-noreply, mcatanzaro, pgorszkowski
Priority: P2 Keywords: HTML5, PlatformOnly
Version: Other   
Hardware: Unspecified   
OS: Linux   
Attachments:
Description Flags
Shaka swapping video variants fail none

Description laurence.ejraee 2023-03-24 07:10:35 PDT 
Created attachment 465569 [details]
Shaka swapping video variants fail

On wpewebkit 2.28 (also seen on 2.22), video playing on latest Shaka player freezes while audio continues playing.
The issue is caused by changing between multiple video variants from the source manifest - which have different (increasing) bandwidths.

Source manifest: https://aaaaaaaaaaaaaaaaaaaaaackipjeaaaaaaaayaaaa.pop-iad-2.cf.dash.row.aiv-cdn.net/dm/2$_xhtKlkIw1Zs1P__FsEORQ39Gxw~/88db/bfd7/f899/478e-b7a9-a58bda78b775/f50d20d5-bdb5-4c9e-a4f6-c45e3c7d7e03_corrected.mpd?encoding=segmentBase&amznDtid=A2YACIV26UKFI2

I have attached a shaka demo html that manually switches between 3 video variants with selectVariantTrack() and the issue can be observed.
In the network tab you should see initial video_X.mp4 being used, then after some time it will move to use video_11.mp4 and then video_12.mp4. Shortly after change to video_12.mp4 the freezing video will be observed.
This demo does not fail on Chrome or Firefox.
Also the issue can be seen with the source url in Shaka player's own demo site: https://shaka-player-demo.appspot.com/demo/
Comment 1 Michael Catanzaro 2023-03-24 08:10:05 PDT 
(In reply to laurence.ejraee from comment #0)
> On wpewebkit 2.28 (also seen on 2.22),

Hi, this version is much too old to be reporting bugs upstream. Feel free to reopen if you can reproduce with 2.40.
Comment 2 Przemyslaw Gorszkowski 2023-03-24 09:33:32 PDT 
Hi,

You should rather report it here: https://github.com/WebPlatformForEmbedded/WPEWebKit/issues
Comment 3 laurence.ejraee 2023-03-24 09:34:34 PDT 
Thanks I'll report there.