Bug 1016148 - Ensure we mark IMFSamples after a flush as discontinuities, so that A/V sync works after seek in MP4Reader. r=padenot

content/media/fmp4/wmf/MFTDecoder.cpp

@@ -21,6 +21,7 @@ namespace mozilla {
 
 MFTDecoder::MFTDecoder()
   : mMFTProvidesOutputSamples(false)
+  , mDiscontinuity(true)
 {
   memset(&mInputStreamInfo, 0, sizeof(MFT_INPUT_STREAM_INFO));
   memset(&mOutputStreamInfo, 0, sizeof(MFT_OUTPUT_STREAM_INFO));
@@ -237,6 +238,11 @@ MFTDecoder::Output(RefPtr<IMFSample>* aOutput)
 
   MOZ_ASSERT(output.pSample);
 
+  if (mDiscontinuity) {
+    output.pSample->SetUINT32(MFSampleExtension_Discontinuity, TRUE);
+    mDiscontinuity = false;
+  }
+
   *aOutput = output.pSample; // AddRefs
   if (mMFTProvidesOutputSamples) {
     // If the MFT is providing samples, we must release the sample here.
@@ -277,6 +283,8 @@ MFTDecoder::Flush()
   HRESULT hr = SendMFTMessage(MFT_MESSAGE_COMMAND_FLUSH, 0);
   NS_ENSURE_TRUE(SUCCEEDED(hr), hr);
 
+  mDiscontinuity = true;
+
   return S_OK;
 }
 

content/media/fmp4/wmf/MFTDecoder.h

@@ -96,6 +96,9 @@ private:
 
   // True if the IMFTransform allocates the samples that it returns.
   bool mMFTProvidesOutputSamples;
+
+  // True if we need to mark the next sample as a discontinuity.
+  bool mDiscontinuity;
 };
 
 } // namespace mozilla