Improve playlist alignment when PDT across playlists is inconsistent #7482
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hongjun-bae
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I understand that this modification was made because simply increasing the tolerance cannot fundamentally resolve cases where the PDT alignment is completely incorrect.
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| const delta = (targetPDT - refPDT) / 1000 - (frag.start - refFrag.start); | ||
| const dateDifference = (targetPDT - refPDT) / 1000; | ||
| if (Math.abs(dateDifference) > Math.max(60, details.totalduration)) { |
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The issue of small timing gaps, such as 352ms, was raised in #7557, but what was the reason for setting the PDT to 60 seconds? Is there a specific reason why “totalduration” was set as the default value? I’m worried that I’m not allowing for enough discontinuities.
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And if the alignment fails like this, logging will be necessary.
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The issue of small timing gaps, such as 352ms, was raised in #7557,
How so? #7557 will be resolved by #7626.
Small gaps will not have a major impact on segment selection. Ultimately, playlists are realigned once video and audio timestamps are known. VTT mapping is not used in alignment. This change only aims to skip alignment using Program-Date-Time when the date times are wildly inconsistent between playlists - more than totalduration would mean there is no overlap, but for very short playlists, we'll enforce a minimum of 60 seconds.
And if the alignment fails like this, logging will be necessary.
Logging can be added before merging.
This PR will...
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