2 files changed, 40 insertions, 4 deletions

diff --git a/dom/media/mediasource/TrackBuffersManager.cpp b/dom/media/mediasource/TrackBuffersManager.cpp
index c87fa239f1..58ba7c250b 100644
--- a/dom/media/mediasource/TrackBuffersManager.cpp
+++ b/dom/media/mediasource/TrackBuffersManager.cpp
@@ -922,7 +922,11 @@ void TrackBuffersManager::SegmentParserLoop() {
       if (mNewMediaSegmentStarted) {
         if (NS_SUCCEEDED(newData) && mLastParsedEndTime.isSome() &&
             start < mLastParsedEndTime.ref()) {
-          MSE_DEBUG("Re-creating demuxer");
+          MSE_DEBUG("Re-creating demuxer, new start (%" PRId64
+                    ") is smaller than last parsed end time (%" PRId64 ")",
+                    start.ToMicroseconds(),
+                    mLastParsedEndTime->ToMicroseconds());
+          mFrameEndTimeBeforeRecreateDemuxer = Some(end);
           ResetDemuxingState();
           return;
         }
@@ -1038,8 +1042,15 @@ void TrackBuffersManager::CreateDemuxerforMIMEType() {
 
   if (mType.Type() == MEDIAMIMETYPE(VIDEO_WEBM) ||
       mType.Type() == MEDIAMIMETYPE(AUDIO_WEBM)) {
-    mInputDemuxer =
-        new WebMDemuxer(mCurrentInputBuffer, true /* IsMediaSource*/);
+    if (mFrameEndTimeBeforeRecreateDemuxer) {
+      MSE_DEBUG(
+          "CreateDemuxerFromMimeType: "
+          "mFrameEndTimeBeforeRecreateDemuxer=%" PRId64,
+          mFrameEndTimeBeforeRecreateDemuxer->ToMicroseconds());
+    }
+    mInputDemuxer = new WebMDemuxer(mCurrentInputBuffer, true,
+                                    mFrameEndTimeBeforeRecreateDemuxer);
+    mFrameEndTimeBeforeRecreateDemuxer.reset();
     DDLINKCHILD("demuxer", mInputDemuxer.get());
     return;
   }
@@ -1047,6 +1058,7 @@ void TrackBuffersManager::CreateDemuxerforMIMEType() {
   if (mType.Type() == MEDIAMIMETYPE(VIDEO_MP4) ||
       mType.Type() == MEDIAMIMETYPE(AUDIO_MP4)) {
     mInputDemuxer = new MP4Demuxer(mCurrentInputBuffer);
+    mFrameEndTimeBeforeRecreateDemuxer.reset();
     DDLINKCHILD("demuxer", mInputDemuxer.get());
     return;
   }
@@ -1625,9 +1637,11 @@ void TrackBuffersManager::MaybeDispatchEncryptedEvent(
 void TrackBuffersManager::OnVideoDemuxCompleted(
     const RefPtr<MediaTrackDemuxer::SamplesHolder>& aSamples) {
   mTaskQueueCapability->AssertOnCurrentThread();
-  MSE_DEBUG("%zu video samples demuxed", aSamples->GetSamples().Length());
   mVideoTracks.mDemuxRequest.Complete();
   mVideoTracks.mQueuedSamples.AppendElements(aSamples->GetSamples());
+  MSE_DEBUG("%zu video samples demuxed, queued-sz=%zu",
+            aSamples->GetSamples().Length(),
+            mVideoTracks.mQueuedSamples.Length());
 
   MaybeDispatchEncryptedEvent(aSamples->GetSamples());
   DoDemuxAudio();
@@ -1892,6 +1906,9 @@ void TrackBuffersManager::ProcessFrames(TrackBuffer& aSamples,
       // coded frame.
       if (!sample->mKeyframe) {
         previouslyDroppedSample = nullptr;
+        SAMPLE_DEBUGV("skipping sample [%" PRId64 ",%" PRId64 "]",
+                      sample->mTime.ToMicroseconds(),
+                      sample->GetEndTime().ToMicroseconds());
         continue;
       }
       // 2. Set the need random access point flag on track buffer to false.
@@ -1971,6 +1988,7 @@ void TrackBuffersManager::ProcessFrames(TrackBuffer& aSamples,
         // 4. Unset the highest end timestamp on all track buffers.
         // 5. Set the need random access point flag on all track buffers to
         // true.
+        MSE_DEBUG("Resetting append state");
         track->ResetAppendState();
       }
       // 6. Jump to the Loop Top step above to restart processing of the current
@@ -2553,10 +2571,12 @@ void TrackBuffersManager::RecreateParser(bool aReuseInitData) {
   mParser = ContainerParser::CreateForMIMEType(mType);
   DDLINKCHILD("parser", mParser.get());
   if (aReuseInitData && mInitData) {
+    MSE_DEBUG("Using existing init data to reset parser");
     TimeUnit start, end;
     mParser->ParseStartAndEndTimestamps(MediaSpan(mInitData), start, end);
     mProcessedInput = mInitData->Length();
   } else {
+    MSE_DEBUG("Resetting parser, not reusing init data");
     mProcessedInput = 0;
   }
 }
@@ -2843,12 +2863,20 @@ const MediaRawData* TrackBuffersManager::GetSample(TrackInfo::TrackType aTrack,
   const TrackBuffer& track = GetTrackBuffer(aTrack);
 
   if (aIndex >= track.Length()) {
+    MSE_DEBUGV(
+        "Can't get sample due to reaching to the end, index=%u, "
+        "length=%zu",
+        aIndex, track.Length());
     // reached the end.
     return nullptr;
   }
 
   if (!(aExpectedDts + aFuzz).IsValid() || !(aExpectedPts + aFuzz).IsValid()) {
     // Time overflow, it seems like we also reached the end.
+    MSE_DEBUGV("Can't get sample due to time overflow, expectedPts=%" PRId64
+               ", aExpectedDts=%" PRId64 ", fuzz=%" PRId64,
+               aExpectedPts.ToMicroseconds(), aExpectedPts.ToMicroseconds(),
+               aFuzz.ToMicroseconds());
     return nullptr;
   }
 
@@ -2859,6 +2887,12 @@ const MediaRawData* TrackBuffersManager::GetSample(TrackInfo::TrackType aTrack,
     return sample;
   }
 
+  MSE_DEBUGV("Can't get sample due to big gap, sample=%" PRId64
+             ", expectedPts=%" PRId64 ", aExpectedDts=%" PRId64
+             ", fuzz=%" PRId64,
+             sample->mTime.ToMicroseconds(), aExpectedPts.ToMicroseconds(),
+             aExpectedPts.ToMicroseconds(), aFuzz.ToMicroseconds());
+
   // Gap is too big. End of Stream or Waiting for Data.
   // TODO, check that we have continuous data based on the sanitized buffered
   // range instead.
diff --git a/dom/media/mediasource/TrackBuffersManager.h b/dom/media/mediasource/TrackBuffersManager.h
index c72f2f5453..0e9c857586 100644
--- a/dom/media/mediasource/TrackBuffersManager.h
+++ b/dom/media/mediasource/TrackBuffersManager.h
@@ -568,6 +568,8 @@ class TrackBuffersManager final
   // mTaskQueue. However, there's special locking around mTaskQueue, so we keep
   // both for now.
   Maybe<EventTargetCapability<TaskQueue>> mTaskQueueCapability;
+
+  Maybe<media::TimeUnit> mFrameEndTimeBeforeRecreateDemuxer;
 };
 
 }  // namespace mozilla