Stop fetching live stream while paused

[yairans]

What version of Shaka Player are you using: latest of demo app

Can you reproduce the issue with our latest release version: yes

Can you reproduce the issue with the latest code from master: yes

Are you using the demo app or your own custom app: demo app

What browser and OS are you using: chrome 60 on macOS Sierra 10.12

What are the manifest and license server URIs: Big Buck Bunny (live) from demo app

What did you do?
load -> pause

What did you expect to happen?
The video.currentTime should remain at the paused position. the video should present the same image until play.

What actually happened?
each downloaded chunk updates the currentTime and the video image.
Note the scrubber, once is reaching to the start it's happening.

[kuznetcoff777]

Approving, when player is paused on live conent, it still downloads video segmetns to update images. It is bug, i suppose, user downloads segments when it is not necessary.

[theifish]

Confirm the bug.
When currentTime reaches lowest available time (video.currentTime < shakaPlayer.seekRange().start), shaka starts to load chunks forward and automatically seeks to last available lowest time untimelly.
It's very annoying behaviour for a user.
I think the proper way is to update mpd file periodically and not to load video/audio chunks, and when user press play, just seeks to last available time (if out of range).

[kuznetcoff777]

@joeyparrish, please answer us

[joeyparrish]

Hi all,

The "needs triage" label means we are aware of the issue but have not reproduced it or scheduled any changes. We will get to this as soon as we can. We apologize for the delay.

[joeyparrish]

It seems that there are two things at work here.

1. If the playhead falls outside the seek range, we force the playhead back in. This is a good thing generally, but perhaps this should be suppressed while paused. If the user pauses a live stream for so long that we fall outside the seek range, we would jump back into the seek range when the user hits play.
2. We continue to buffer while paused. This is also generally a good thing. Imagine you want to pause the content specifically to let it buffer. Perhaps adaptation is turned off and the player is forced to a high resolution, or perhaps there is no stream with low enough bandwidth for you and you are a patient user. So we don't want to stop buffering when paused. But perhaps we should consider an exception where if paused and outside the seek range, we stop buffering. This would be more work than point 1 above, and have less effect since buffering while paused will always stop once the buffering goal it hit.

For now, I propose that we suppress forced seeks based on the seek range while paused. (This is in shaka.media.Playhead.) I expect this will be enough, but if not, we can explore changes to StreamingEngine as well.

Tentatively scheduled for v2.3.

[kuznetcoff777]

"But perhaps we should consider an exception where if paused and outside the seek range, we stop buffering." - what if there will be long DVR, for exampe 24 hours? It will still download for 24 hours. I propose to dome some configurable parameter, that configures x seconds timeout after which not to download new segments after x seconds of being paused.

[joeyparrish]

what if there will be long DVR, for example 24 hours? It will still download for 24 hours. I propose to dome some configurable parameter, that configures x seconds timeout after which not to download new segments after x seconds of being paused.

No, it wouldn't download for 24 hours in that scenario. If the buffering goal were set to 60 seconds, it would only download 60 seconds of content ahead of the playhead. If we are paused, the playhead wouldn't move (change 1 above) and we'd stop buffering soon.

So in essence, the parameter you propose already exists: streaming.bufferingGoal Does that make sense?

[kuznetcoff777]

O, thats fine