WebM file with Vorbis track plays in burst

https://bugs.webkit.org/show_bug.cgi?id=273866 rdar://124880261 Reviewed by Eric Carlson. Add support for Block containing multiple frames. Previously we would create as many CMSampleBuffer as found in the block, but all those samples would have the timestamp of the Block. We now accrue the duration of each frame and properly increment the sample's timestamp accordingly. Manually verified that file plays okay * Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.cpp: (WebCore::WebMParser::OnSimpleBlockBegin): (WebCore::WebMParser::OnSimpleBlockEnd): (WebCore::WebMParser::OnFrame): (WebCore::WebMParser::VideoTrackData::consumeFrameData): (WebCore::WebMParser::AudioTrackData::consumeFrameData): * Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.h: (WebCore::WebMParser::TrackData::consumeFrameData): Canonical link: https://commits.webkit.org/278665@main
WebKit · May 12, 2024 · 6a9c5f8 · 6a9c5f8
1 parent eb34966
commit 6a9c5f8
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Showing 2 changed files with 17 additions and 7 deletions.
diff --git a/Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.cpp b/Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.cpp
@@ -925,6 +925,7 @@ webm::Status WebMParser::OnSimpleBlockBegin(const ElementMetadata&, const Simple
     *action = Action::kRead;
 
     m_currentBlock = std::make_optional<BlockVariant>(SimpleBlock(block));
+    m_currentDuration = MediaTime::zeroTime();
 
     return Status(Status::kOkCompleted);
 }
@@ -934,6 +935,7 @@ webm::Status WebMParser::OnSimpleBlockEnd(const ElementMetadata&, const SimpleBl
     INFO_LOG_IF_POSSIBLE(LOGIDENTIFIER);
 
     m_currentBlock = std::nullopt;
+    m_currentDuration = MediaTime::zeroTime();
 
     return Status(Status::kOkCompleted);
 }
@@ -1003,7 +1005,11 @@ webm::Status WebMParser::OnFrame(const FrameMetadata& metadata, Reader* reader,
         return Skip(reader, bytesRemaining);
     }
 
-    return trackData->consumeFrameData(*reader, metadata, bytesRemaining, MediaTime(block->timecode + m_currentTimecode, m_timescale));
+    auto result = trackData->consumeFrameData(*reader, metadata, bytesRemaining, MediaTime(block->timecode + m_currentTimecode, m_timescale) + m_currentDuration);
+    if (std::holds_alternative<webm::Status>(result))
+        return std::get<webm::Status>(result);
+    m_currentDuration += std::get<MediaTime>(result);
+    return Status(Status::kOkCompleted);
 }
 
 
@@ -1067,7 +1073,7 @@ void WebMParser::VideoTrackData::resetCompletedFramesState()
     TrackData::resetCompletedFramesState();
 }
 
-webm::Status WebMParser::VideoTrackData::consumeFrameData(webm::Reader& reader, const FrameMetadata& metadata, uint64_t* bytesRemaining, const MediaTime& presentationTime)
+WebMParser::ConsumeFrameDataResult WebMParser::VideoTrackData::consumeFrameData(webm::Reader& reader, const FrameMetadata& metadata, uint64_t* bytesRemaining, const MediaTime& presentationTime)
 {
 #if ENABLE(VP9)
     auto status = readFrameData(reader, metadata, bytesRemaining);
@@ -1203,7 +1209,7 @@ void WebMParser::AudioTrackData::resetCompletedFramesState()
     TrackData::resetCompletedFramesState();
 }
 
-webm::Status WebMParser::AudioTrackData::consumeFrameData(webm::Reader& reader, const FrameMetadata& metadata, uint64_t* bytesRemaining, const MediaTime& presentationTime)
+WebMParser::ConsumeFrameDataResult WebMParser::AudioTrackData::consumeFrameData(webm::Reader& reader, const FrameMetadata& metadata, uint64_t* bytesRemaining, const MediaTime& presentationTime)
 {
     auto status = readFrameData(reader, metadata, bytesRemaining);
     if (!status.completed_ok())
@@ -1329,7 +1335,7 @@ webm::Status WebMParser::AudioTrackData::consumeFrameData(webm::Reader& reader,
     drainPendingSamples();
 
     ASSERT(!*bytesRemaining);
-    return webm::Status(webm::Status::kOkCompleted);
+    return packetDuration;
 }
 
 

diff --git a/Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.h b/Source/WebCore/platform/graphics/cocoa/SourceBufferParserWebM.h
@@ -122,6 +122,8 @@ class WebMParser
         Opus,
     };
 
+    using ConsumeFrameDataResult = std::variant<MediaTime, webm::Status>;
+
     class TrackData {
         WTF_MAKE_FAST_ALLOCATED;
     public:
@@ -154,7 +156,8 @@ class WebMParser
 
         WebMParser& parser() const { return m_parser; }
 
-        virtual webm::Status consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&)
+        using ConsumeFrameDataResult = WebMParser::ConsumeFrameDataResult;
+        virtual ConsumeFrameDataResult consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&)
         {
             ASSERT_NOT_REACHED();
             return webm::Status(webm::Status::kInvalidElementId);
@@ -221,7 +224,7 @@ class WebMParser
 
     private:
         ASCIILiteral logClassName() const { return "VideoTrackData"_s; }
-        webm::Status consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&) final;
+        ConsumeFrameDataResult consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&) final;
         void resetCompletedFramesState() final;
         void processPendingMediaSamples(const MediaTime&);
         WTF::Deque<MediaSamplesBlock::MediaSampleItem> m_pendingMediaSamples;
@@ -244,7 +247,7 @@ class WebMParser
         ~AudioTrackData();
 
     private:
-        webm::Status consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&) final;
+        ConsumeFrameDataResult consumeFrameData(webm::Reader&, const webm::FrameMetadata&, uint64_t*, const MediaTime&) final;
         void resetCompletedFramesState() final;
         ASCIILiteral logClassName() const { return "AudioTrackData"_s; }
 
@@ -296,6 +299,7 @@ class WebMParser
     bool m_initializationSegmentProcessed { false };
     uint32_t m_timescale { 1000 };
     uint64_t m_currentTimecode { 0 };
+    MediaTime m_currentDuration;
 
     State m_state { State::None };