Bug 1336431: P5. Re-add ConfigurationChanged API. r=JamesCheng

We need to inform the MediaDataDecoder that a new sample configuration has been detected.
To do so, and to ensure that samples are easily matched to a given configuration, we first drain the decoder prior feeding a new frame.

MozReview-Commit-ID: Hye251CF21i

--HG--
extra : rebase_source : d6e5be74a6678cef0ff4c798fac91d95911be70a

dom/media/MediaFormatReader.cpp

@@ -289,6 +289,10 @@ public:
   {
     return mDecoder->SupportDecoderRecycling();
   }
+  void ConfigurationChanged(const TrackInfo& aConfig) override
+  {
+    mDecoder->ConfigurationChanged(aConfig);
+  }
   RefPtr<ShutdownPromise> Shutdown() override
   {
     RefPtr<MediaDataDecoder> decoder = mDecoder.forget();
@@ -1760,19 +1764,15 @@ MediaFormatReader::HandleDemuxedSamples(
     RefPtr<TrackInfoSharedPtr> info = sample->mTrackInfo;
 
     if (info && decoder.mLastStreamSourceID != info->GetID()) {
-      bool supportRecycling = MediaPrefs::MediaDecoderCheckRecycling()
-                              && decoder.mDecoder->SupportDecoderRecycling();
       if (decoder.mNextStreamSourceID.isNothing()
           || decoder.mNextStreamSourceID.ref() != info->GetID()) {
-        if (!supportRecycling) {
-          LOG("%s stream id has changed from:%d to:%d, draining decoder.",
-            TrackTypeToStr(aTrack), decoder.mLastStreamSourceID,
-            info->GetID());
-          decoder.RequestDrain();
-          decoder.mNextStreamSourceID = Some(info->GetID());
-          ScheduleUpdate(aTrack);
-          return;
-        }
+        LOG("%s stream id has changed from:%d to:%d, draining decoder.",
+          TrackTypeToStr(aTrack), decoder.mLastStreamSourceID,
+          info->GetID());
+        decoder.RequestDrain();
+        decoder.mNextStreamSourceID = Some(info->GetID());
+        ScheduleUpdate(aTrack);
+        return;
       }
 
       LOG("%s stream id has changed from:%d to:%d.",
@@ -1780,9 +1780,9 @@ MediaFormatReader::HandleDemuxedSamples(
           info->GetID());
       decoder.mLastStreamSourceID = info->GetID();
       decoder.mNextStreamSourceID.reset();
-      decoder.mInfo = info;
 
-      if (!supportRecycling) {
+      if (!MediaPrefs::MediaDecoderCheckRecycling()
+          || !decoder.mDecoder->SupportDecoderRecycling()) {
         LOG("Decoder does not support recycling, recreate decoder.");
         // If flushing is required, it will clear our array of queued samples.
         // So make a copy now.
@@ -1791,8 +1791,13 @@ MediaFormatReader::HandleDemuxedSamples(
         if (sample->mKeyframe) {
           decoder.mQueuedSamples.AppendElements(Move(samples));
         }
+      } else if (decoder.mInfo && *decoder.mInfo != *info) {
+        const TrackInfo* trackInfo = *info;
+        decoder.mDecoder->ConfigurationChanged(*trackInfo);
       }
 
+      decoder.mInfo = info;
+
       if (sample->mKeyframe) {
         ScheduleUpdate(aTrack);
       } else {

dom/media/platforms/PlatformDecoderModule.h

@@ -283,7 +283,6 @@ public:
     return false;
   }
 
-
   // Return the name of the MediaDataDecoder, only used for decoding.
   // Only return a static const string, as the information may be accessed
   // in a non thread-safe fashion.
@@ -302,6 +301,21 @@ public:
   // Reuse the decoder if the decoder support recycling.
   // Currently, only Android video decoder will return true.
   virtual bool SupportDecoderRecycling() const { return false; }
+
+  // ConfigurationChanged will be called to inform the video or audio decoder
+  // that the format of the next input sample is about to change.
+  // If video decoder, aConfig will be a VideoInfo object.
+  // If audio decoder, aConfig will be a AudioInfo object.
+  // It is not safe to store a reference to this object and the decoder must
+  // make a copy.
+  // Care should be taken as ConfigurationChanged is called on the reader's
+  // taskqueue.
+  virtual void ConfigurationChanged(const TrackInfo& aConfig)
+  {
+    MOZ_ASSERT(SupportDecoderRecycling(),
+               "Can only work with a decoder supporting recycling.");
+  }
+
 };
 
 } // namespace mozilla

dom/media/platforms/wrappers/H264Converter.cpp

@@ -19,6 +19,7 @@ namespace mozilla
 H264Converter::H264Converter(PlatformDecoderModule* aPDM,
                              const CreateDecoderParams& aParams)
   : mPDM(aPDM)
+  , mOriginalConfig(aParams.VideoConfig())
   , mCurrentConfig(aParams.VideoConfig())
   , mKnowsCompositor(aParams.mKnowsCompositor)
   , mImageContainer(aParams.mImageContainer)
@@ -199,7 +200,7 @@ H264Converter::CreateDecoder(DecoderDoctorDiagnostics* aDiagnostics)
   }
 
   mDecoder = mPDM->CreateVideoDecoder({
-    mCurrentConfig,
+    mUseOriginalConfig ? mOriginalConfig : mCurrentConfig,
     mTaskQueue,
     aDiagnostics,
     mImageContainer,
@@ -214,6 +215,7 @@ H264Converter::CreateDecoder(DecoderDoctorDiagnostics* aDiagnostics)
     return NS_ERROR_FAILURE;
   }
 
+  mUseOriginalConfig = false;
   mNeedKeyframe = true;
 
   return NS_OK;
@@ -250,31 +252,7 @@ H264Converter::OnDecoderInitDone(const TrackType aTrackType)
 {
   mInitPromiseRequest.Complete();
   RefPtr<MediaRawData> sample = mPendingSample.forget();
-  if (mNeedKeyframe && !sample->mKeyframe) {
-    mDecodePromise.Resolve(DecodedData(), __func__);
-    return;
-  }
-  mNeedKeyframe = false;
-  if (!mNeedAVCC
-      && !mp4_demuxer::AnnexB::ConvertSampleToAnnexB(sample, mNeedKeyframe)) {
-    mDecodePromise.Reject(
-      MediaResult(NS_ERROR_OUT_OF_MEMORY,
-                  RESULT_DETAIL("ConvertSampleToAnnexB")),
-      __func__);
-    return;
-  }
-  RefPtr<H264Converter> self = this;
-  mDecoder->Decode(sample)
-    ->Then(AbstractThread::GetCurrent()->AsTaskQueue(), __func__,
-           [self, this](const MediaDataDecoder::DecodedData& aResults) {
-             mDecodePromiseRequest.Complete();
-             mDecodePromise.Resolve(aResults, __func__);
-           },
-           [self, this](const MediaResult& aError) {
-             mDecodePromiseRequest.Complete();
-             mDecodePromise.Reject(aError, __func__);
-           })
-    ->Track(mDecodePromiseRequest);
+  DecodeFirstSample(sample);
 }
 
 void
@@ -287,6 +265,39 @@ H264Converter::OnDecoderInitFailed(const MediaResult& aError)
     __func__);
 }
 
+void
+H264Converter::DecodeFirstSample(MediaRawData* aSample)
+{
+  if (mNeedKeyframe && !aSample->mKeyframe) {
+    mDecodePromise.Resolve(DecodedData(), __func__);
+    return;
+  }
+  mNeedKeyframe = false;
+  if (!mNeedAVCC
+      && !mp4_demuxer::AnnexB::ConvertSampleToAnnexB(aSample, mNeedKeyframe)) {
+    mDecodePromise.Reject(
+      MediaResult(NS_ERROR_OUT_OF_MEMORY,
+                  RESULT_DETAIL("ConvertSampleToAnnexB")),
+      __func__);
+    return;
+  }
+  if (CanRecycleDecoder()) {
+    mDecoder->ConfigurationChanged(mCurrentConfig);
+  }
+  RefPtr<H264Converter> self = this;
+  mDecoder->Decode(aSample)
+    ->Then(AbstractThread::GetCurrent()->AsTaskQueue(), __func__,
+           [self, this](const MediaDataDecoder::DecodedData& aResults) {
+             mDecodePromiseRequest.Complete();
+             mDecodePromise.Resolve(aResults, __func__);
+           },
+           [self, this](const MediaResult& aError) {
+             mDecodePromiseRequest.Complete();
+             mDecodePromise.Reject(aError, __func__);
+           })
+    ->Track(mDecodePromiseRequest);
+}
+
 nsresult
 H264Converter::CheckForSPSChange(MediaRawData* aSample)
 {
@@ -298,16 +309,39 @@ H264Converter::CheckForSPSChange(MediaRawData* aSample)
         return NS_OK;
       }
 
-  if (MediaPrefs::MediaDecoderCheckRecycling()
-      && mDecoder->SupportDecoderRecycling()) {
+  mPendingSample = aSample;
+
+  if (CanRecycleDecoder()) {
     // Do not recreate the decoder, reuse it.
     UpdateConfigFromExtraData(extra_data);
+    // Ideally we would want to drain the decoder instead of flushing it.
+    // However the draining operation requires calling Drain and looping several
+    // times which isn't possible from within the H264Converter. So instead we
+    // flush the decoder. In practice, this is a no-op as SPS change will only
+    // be used with MSE. And with MSE, the MediaFormatReader would have drained
+    // the decoder already.
+    RefPtr<H264Converter> self = this;
+    mDecoder->Flush()
+      ->Then(AbstractThread::GetCurrent()->AsTaskQueue(),
+             __func__,
+             [self, this]() {
+               mFlushRequest.Complete();
+               DecodeFirstSample(mPendingSample);
+               mPendingSample = nullptr;
+             },
+             [self, this](const MediaResult& aError) {
+               mFlushRequest.Complete();
+               mDecodePromise.Reject(aError, __func__);
+             })
+      ->Track(mFlushRequest);
     mNeedKeyframe = true;
-    return NS_OK;
+    // This is not really initializing the decoder, but it will do as it
+    // indicates an operation is pending.
+    return NS_ERROR_DOM_MEDIA_INITIALIZING_DECODER;
   }
+
   // The SPS has changed, signal to flush the current decoder and create a
   // new one.
-  mPendingSample = aSample;
   RefPtr<H264Converter> self = this;
   mDecoder->Flush()
     ->Then(AbstractThread::GetCurrent()->AsTaskQueue(),

dom/media/platforms/wrappers/H264Converter.h

@@ -47,7 +47,12 @@ public:
     }
     return false;
   }
-
+  void ConfigurationChanged(const TrackInfo& aConfig) override
+  {
+    if (mDecoder && mDecoder->SupportDecoderRecycling()) {
+      mDecoder->ConfigurationChanged(aConfig);
+    }
+  }
   nsresult GetLastError() const { return mLastError; }
 
 private:
@@ -62,7 +67,17 @@ private:
   void OnDecoderInitDone(const TrackType aTrackType);
   void OnDecoderInitFailed(const MediaResult& aError);
 
+  bool CanRecycleDecoder() const
+  {
+    MOZ_ASSERT(mDecoder);
+    return MediaPrefs::MediaDecoderCheckRecycling()
+           && mDecoder->SupportDecoderRecycling();
+  }
+
+  void DecodeFirstSample(MediaRawData* aSample);
+
   RefPtr<PlatformDecoderModule> mPDM;
+  const VideoInfo mOriginalConfig;
   VideoInfo mCurrentConfig;
   RefPtr<layers::KnowsCompositor> mKnowsCompositor;
   RefPtr<layers::ImageContainer> mImageContainer;
@@ -80,6 +95,8 @@ private:
   bool mNeedAVCC;
   nsresult mLastError;
   bool mNeedKeyframe = true;
+  // Set to true once a decoder has been created.
+  bool mUseOriginalConfig = true;
   const TrackInfo::TrackType mType;
   MediaEventProducer<TrackInfo::TrackType>* const mOnWaitingForKeyEvent;
 };