Bug 256038 - For Linear content When there is a transition from Ad to content <-> content to Ad, there is momentary freeze.
Summary: For Linear content When there is a transition from Ad to content <-> content ...
Status: RESOLVED MOVED
Alias: None
Product: WebKit
Classification: Unclassified
Component: Media (show other bugs)
Version: Safari Technology Preview
Hardware: Unspecified Unspecified
: P1 Blocker
Assignee: Nobody
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2023-04-27 04:59 PDT by Ashutosh Kumar
Modified: 2023-06-08 12:51 PDT (History)
5 users (show)

See Also:


Attachments
same video for the reference where issue is at 00:11 (18.59 MB, video/mp4)
2023-05-08 08:31 PDT, Ashutosh Kumar
no flags Details

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Description Ashutosh Kumar 2023-04-27 04:59:17 PDT
We have observed for the linear content whenever there is transition from Ad to content <-> content to Ad, there is momentary freeze.

The player state was proper during the transition (it was not going to stalled/buffering state).
No network errors found during momentary freeze.

On analyzing the base media decode time of the content segments (.mp4), we found that it is consistent with the #EXT-X-PROGRAM-DATE-TIME present in the manifest. The base media decode time of the ad segments however had static values (being vod), which we were not able to directly map with their corresponding EXT-X-PROGRAM-DATE-TIME values. But we do not suspect anything wrong here as the ad itself would not have played if the base media decode times were incorrect.

Is there any such known issue ?
Comment 1 Alexey Proskuryakov 2023-04-27 17:33:08 PDT
Thank you for the report! Could you please provide steps to reproduce?
Comment 2 Ashutosh Kumar 2023-04-27 21:33:13 PDT
Play a liner content which having server side Ad, once Ad will get over Content play back starts. During Ad to content switch for quater second there a freeze.
Comment 3 Alexey Proskuryakov 2023-04-28 08:28:34 PDT
By steps to reproduce, I mean something in the form of "load this particular URL in Safari, click here, observe this problem". Re-creating a test from the current description would be a significant effort.
Comment 4 Radar WebKit Bug Importer 2023-05-04 05:00:19 PDT
<rdar://problem/108887725>
Comment 5 Ashutosh Kumar 2023-05-08 08:31:20 PDT
Created attachment 466281 [details]
same video for the reference where issue is at 00:11
Comment 6 Ashutosh Kumar 2023-05-08 08:32:28 PDT
Hi Alexey Proskuryakov,

Below is the stream where Momentary freeze is seen during Ad to Content transition.
https://linear-dai-ott-ap.ssai.iris.synamedia.com/tenant/jvkyf329/d3qah5otyky386.cloudfront.net/wm-clear/hls-mp4/loki-dashiso-clear/6005/default.m3u8?PID=&PAID=6000&deviceId=6ec3963b3ba57cb7f23fd7b848a62e5d&sessionId=abr-linear-5cfe3fab-b2f1-4f8a-9c82-69asdfasdf7e&optin=true&hhid=4f66ecasdfasdcb5bc287290118f154ed1&daiEnabled=true


For the stream Ad appears every 3 minutes and lasts for 30 seconds.

I have also attached same video for the reference where issue is at 00:11
Comment 7 Ashutosh Kumar 2023-05-11 00:21:38 PDT
Is there any update?
Comment 8 Ashutosh Kumar 2023-05-11 03:57:27 PDT
There is an important observation.

If we play the dataplane stream directly with CUE-IN/CUE-OUT tags - there is no momentary freeze.
Freeze happens only if discontinuity tag is present in the playlist. 

 

Could you please confirm if reinitializing decoder with init segment is causing any issues?

We are eagerly waiting fir this, Quick response will be appreciated.


Thanks,
Ashutosh
Comment 9 Ashutosh Kumar 2023-05-14 22:40:15 PDT
Hi,

I have found the crucial factor: It seems that Safari native player expects that the PTS of the video after the DISCONTINUITY is AT LEAST as high as the PTS of the audio after the DISCONTINUITY.

Could you please confirm is this expected ?
Comment 10 Ashutosh Kumar 2023-05-16 06:53:09 PDT
Any update?
Comment 11 Alexey Proskuryakov 2023-05-17 10:51:51 PDT
Thank you for the updates.

This is believed to be an issue in Apple frameworks below WebKit, so I'm marking it is resolved/moved. Please continue investigating this with Apple.
Comment 12 Brent Fulgham 2023-06-08 12:51:01 PDT
This is actually being tracked internally as:
<rdar://108836157>