Fix Low-Latency HLS VTT subtitle part loading #7626
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Fix fragment selection when live subtitle playlist does not overlap with position (#7557) Fix subtitle selection in asset players while primary is detached
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hongjun-bae
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hongjun-bae
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This PR helps address the issue related to the previous track=undefined setting and the lenient subtitle controller.
| ); | ||
| if (!foundFrag) { | ||
| this.warn('Subtitle playlist not aligned with playback'); | ||
| track.details = undefined; |
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The logic for streaming subtitles in LL-HLS has become much more lenient 👍
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Additional changes in #7482 will help to ensure proper playlist alignment. When combined with these changes, audio and subtitle segment loading will follow more of the same logic.
| } | ||
| if (this.waitForLive(track)) { | ||
| const { currentTrackId, levels } = this; | ||
| const track = levels?.[currentTrackId]; |
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Before there was a check to see if track is undefined, now it's removed here. I believe this may cause issues. We may need to keep what was here previously:
if (!track || !levels.length || !track.details) { return; }
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We're covered by track?.details and !trackDetails. No details, no track.
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Got it. that's true that the original code had that: !track.details
| { | ||
| private currentTrackId: number = -1; | ||
| private tracksBuffered: Array<TimeRange[]> = []; | ||
| private tracksBuffered: Array<TimeRange[] | undefined> = []; |
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I don't see anywhere where we are appending an undefined object to tracksBuffered? Do we suspect we need this?
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We don't append undefined values, but we do not use noUncheckedIndexedAccess either. When using (@typescript-eslint/) no-unnecessary-condition (I use this offline, but not in the project proper), typing this way helps by signaling that the result to tracksBuffered[<missing-key-or-index>] may be undefined. Yes, it is bad typing, but simpler safety. I'm open to suggestions - short and long term.
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Got it, I think this is fine for now. And agree maybe something to look into in the future.
…te will never be PARTIAL
This PR will...
Why is this Pull Request needed?
These changes unify subtitle segment finding with audio and video, fixing issues with subtitle part and segment loading.
Are there any points in the code the reviewer needs to double check?
Low-latency live with VTT parts https://llhls-demo.ovenmediaengine.com/app/stream/llhls.m3u8
Resolves issues:
Checklist