commit | c316ca26ddb1a4ad63ce1285ce9cb271c604816a | [log] [tgz] |
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author | jer.noble@apple.com <jer.noble@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> | Fri Jan 17 21:03:55 2020 +0000 |
committer | jer.noble@apple.com <jer.noble@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> | Fri Jan 17 21:03:55 2020 +0000 |
tree | 1e9f7e78eea210064c19a0a19d806448bd81ed1f | |
parent | e5205a33ad940dafdb4fab5d7ea875f3f7a241c2 [diff] |
[MSE] Decode glitches when watching videos on CNN.com https://bugs.webkit.org/show_bug.cgi?id=206412 <rdar://problem/55685630> Reviewed by Xabier Rodriguez-Calvar. Source/WebCore: Test: media/media-source/media-source-samples-out-of-order.html The "Coded frame processing" algorithm has a known shortcoming <https://github.com/w3c/media-source/issues/187> when dealing appends of with "SAP Type 2" content, or in general terms, appending data where the resulting samples have presentation times that do not increase monotonically. When this occurs, the ordering of samples in presentation time will be different from the ordering of samples in decode time. The decoder requires samples to be enqueued in decode time order, but the MSE specification only checks for overlapping samples in presentation time order. During appends of out-of-order samples, this can lead to new samples being inserted between a previously appended sample and the sample on which that sample depends. To resolve this, add a new step in the implementation of the "coded frame processing" algorithm in SourceBuffer::sourceBufferPrivateDidReceiveSample(). When the incoming frame is a sync sample, search forward in the TrackBuffer for all previous samples in between the new sync sample, and the next sync sample. All the samples found in this step would fail to decode correctly if enqueued after the new (possibly different resolution) sync sample, so they are removed in this step. * Modules/mediasource/SampleMap.cpp: (WebCore::DecodeOrderSampleMap::findSampleAfterDecodeKey): * Modules/mediasource/SampleMap.h: * Modules/mediasource/SourceBuffer.cpp: (WebCore::SourceBuffer::sourceBufferPrivateDidReceiveSample): LayoutTests: * media/media-source/media-source-samples-out-of-order-expected.txt: Added. * media/media-source/media-source-samples-out-of-order.html: Added. git-svn-id: http://svn.webkit.org/repository/webkit/trunk@254761 268f45cc-cd09-0410-ab3c-d52691b4dbfc
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