| <!DOCTYPE html> |
| <html> |
| <head> |
| <title>media-source-append-pt-collision-tail</title> |
| <script src="mp4-generator.js"></script> |
| <script src="../video-test.js"></script> |
| <script> |
| // Real-MP4 regression coverage for the proposed MSE Coded Frame |
| // Processing amendment w3c/media-source#375 (presentation-timestamp |
| // collision cleanup). |
| // |
| // When an incoming sample's (DTS, PT) coincides with the existing |
| // sample at the END of the buffer, none of the spec's existing |
| // cleanup steps in SourceBufferPrivate::processMediaSample populate |
| // erasedSamples: |
| // - step 1.13 only fires post-reset (lastDTS invalid) |
| // - step 1.14-first only fires post-reset (highestPT invalid) |
| // - step 1.14-third's range [highestPT, frameEnd-tol) sits past the |
| // colliding sample at the buffer tail (highestPT - tol ≈ existing |
| // sample's PT + dur - 1ms is well above incoming.PT for any |
| // duration > 1ms) |
| // - the cascade's findSampleAfterDecodeKey returns end() |
| // |
| // Without the unconditional #375 pass the trackBuffer.addSample of |
| // the incoming sample silently no-ops (SampleMap is std::map-backed |
| // and the duplicate-key insert collapses); with the fix the existing |
| // sample is evicted first and the new sample inserts successfully. |
| // |
| // Shape (timescale=1000): |
| // Seg 1: one sync sample at baseDecodeTime=2000 dur=1000 CTO=0 |
| // -> DTS=2000 PTS=2000 (interval [2000, 3000)). |
| // Seg 2: one sync sample at baseDecodeTime=2000 dur=500 CTO=0 |
| // -> DTS=2000 PTS=2000 (interval [2000, 2500)). |
| // |
| // Detection via sourceBuffer.buffered.end(0): |
| // - bug present: 3.0 (seg 1's sample preserved with dur=1000) |
| // - bug fixed: 2.5 (seg 1's sample evicted, seg 2's dur=500 wins) |
| // |
| // Timestamps shifted past t=1s so seg 2's DTS is non-zero, avoiding |
| // Source/WebCore/platform/graphics/gstreamer/mse/AppendPipeline.cpp's |
| // extendToTheBeginning hack (which fires on DTS==0 && PTS>0 && sync). |
| |
| var source, sourceBuffer, init, segment1, segment2; |
| |
| async function runTest() { |
| findMediaElement(); |
| if (!MediaSource.isTypeSupported(MP4.VIDEO_TYPE)) { |
| failTest(`${MP4.VIDEO_TYPE} is not supported`); |
| return; |
| } |
| source = new MediaSource(); |
| run('video.src = URL.createObjectURL(source)'); |
| await waitFor(source, 'sourceopen'); |
| run(`sourceBuffer = source.addSourceBuffer('${MP4.VIDEO_TYPE}')`); |
| |
| init = MP4.initSegment({ |
| timescale: 1000, |
| tracks: [{ id: 1, type: 'video', timescale: 1000 }], |
| }); |
| segment1 = MP4.mediaSegment({ |
| sequenceNumber: 1, |
| tracks: [{ |
| id: 1, type: 'video', baseDecodeTime: 2000, |
| samples: [{ duration: 1000, compositionTimeOffset: 0, isSync: true }], |
| }], |
| }); |
| run('sourceBuffer.appendBuffer(MP4.concat(init, segment1))'); |
| await waitFor(sourceBuffer, 'updateend'); |
| testExpected('sourceBuffer.buffered.length', 1); |
| testExpectedEqualWithTolerance('sourceBuffer.buffered.start(0)', 2.0, 0.01); |
| testExpectedEqualWithTolerance('sourceBuffer.buffered.end(0)', 3.0, 0.01); |
| |
| segment2 = MP4.mediaSegment({ |
| sequenceNumber: 2, |
| tracks: [{ |
| id: 1, type: 'video', baseDecodeTime: 2000, |
| samples: [{ duration: 500, compositionTimeOffset: 0, isSync: true }], |
| }], |
| }); |
| run('sourceBuffer.appendBuffer(segment2)'); |
| await waitFor(sourceBuffer, 'updateend'); |
| |
| // #375 must evict seg 1's sample so seg 2's shorter sample wins. |
| testExpected('sourceBuffer.buffered.length', 1); |
| testExpectedEqualWithTolerance('sourceBuffer.buffered.start(0)', 2.0, 0.01); |
| testExpectedEqualWithTolerance('sourceBuffer.buffered.end(0)', 2.5, 0.01); |
| |
| endTest(); |
| } |
| </script> |
| </head> |
| <body onload="runTest()"> |
| <video></video> |
| </body> |
| </html> |
