Bug 935774 - Assertion failure: meta in mozilla::MediaEncoder::GetEncodedData. r=roc

content/media/MediaRecorder.cpp

@@ -79,11 +79,13 @@ class MediaRecorder::Session: public nsIObserver
       MOZ_ASSERT(NS_IsMainThread());
 
       MediaRecorder *recorder = mSession->mRecorder;
+      if (mSession->IsEncoderError()) {
+        recorder->NotifyError(NS_ERROR_UNEXPECTED);
+      }
       nsresult rv = recorder->CreateAndDispatchBlobEvent(mSession);
       if (NS_FAILED(rv)) {
         recorder->NotifyError(rv);
       }
-
       return NS_OK;
     }
 
@@ -225,6 +227,13 @@ public:
     return mEncodedBufferCache->ExtractBlob(mimeType);
   }
 
+  bool IsEncoderError()
+  {
+    if (mEncoder && mEncoder->HasError()) {
+      return true;
+    }
+    return false;
+  }
 private:
 
   // Pull encoded meida data from MediaEncoder and put into EncodedBufferCache.

content/media/encoder/MediaEncoder.cpp

@@ -148,7 +148,7 @@ MediaEncoder::CreateEncoder(const nsAString& aMIMEType)
  *       If this is the last packet of input stream
  *         Set mState to ENCODE_DONE
  *
- *   If mState is ENCODE_DONE
+ *   If mState is ENCODE_DONE or ENCODE_ERROR
  *     Stop the loop
  */
 void
@@ -164,17 +164,23 @@ MediaEncoder::GetEncodedData(nsTArray<nsTArray<uint8_t> >* aOutputBufs,
     switch (mState) {
     case ENCODE_METADDATA: {
       nsRefPtr<TrackMetadataBase> meta = mAudioEncoder->GetMetadata();
-      MOZ_ASSERT(meta);
+      if (meta == nullptr) {
+        LOG("ERROR! AudioEncoder get null Metadata!");
+        mState = ENCODE_ERROR;
+        break;
+      }
       nsresult rv = mWriter->SetMetadata(meta);
       if (NS_FAILED(rv)) {
-       mState = ENCODE_DONE;
+       LOG("ERROR! writer can't accept audio metadata!");
+       mState = ENCODE_ERROR;
        break;
       }
 
       rv = mWriter->GetContainerData(aOutputBufs,
                                      ContainerWriter::GET_HEADER);
       if (NS_FAILED(rv)) {
-       mState = ENCODE_DONE;
+       LOG("ERROR! writer fail to generate header!");
+       mState = ENCODE_ERROR;
        break;
       }
 
@@ -188,7 +194,7 @@ MediaEncoder::GetEncodedData(nsTArray<nsTArray<uint8_t> >* aOutputBufs,
       if (NS_FAILED(rv)) {
         // Encoding might be canceled.
         LOG("ERROR! Fail to get encoded data from encoder.");
-        mState = ENCODE_DONE;
+        mState = ENCODE_ERROR;
         break;
       }
       rv = mWriter->WriteEncodedTrack(encodedData,
@@ -196,7 +202,7 @@ MediaEncoder::GetEncodedData(nsTArray<nsTArray<uint8_t> >* aOutputBufs,
                                       ContainerWriter::END_OF_STREAM : 0);
       if (NS_FAILED(rv)) {
         LOG("ERROR! Fail to write encoded track to the media container.");
-        mState = ENCODE_DONE;
+        mState = ENCODE_ERROR;
         break;
       }
 
@@ -217,7 +223,11 @@ MediaEncoder::GetEncodedData(nsTArray<nsTArray<uint8_t> >* aOutputBufs,
       mShutdown = true;
       reloop = false;
       break;
-
+    case ENCODE_ERROR:
+      LOG("ERROR! MediaEncoder got error!");
+      mShutdown = true;
+      reloop = false;
+      break;
     default:
       MOZ_CRASH("Invalid encode state");
     }

content/media/encoder/MediaEncoder.h

@@ -54,6 +54,7 @@ public :
     ENCODE_METADDATA,
     ENCODE_TRACK,
     ENCODE_DONE,
+    ENCODE_ERROR,
   };
 
   MediaEncoder(ContainerWriter* aWriter,
@@ -121,6 +122,11 @@ public :
     }
   }
 
+  bool HasError()
+  {
+    return mState == ENCODE_ERROR;
+  }
+
 private:
   nsAutoPtr<ContainerWriter> mWriter;
   nsAutoPtr<AudioTrackEncoder> mAudioEncoder;

content/media/encoder/OpusTrackEncoder.cpp

@@ -132,18 +132,17 @@ OpusTrackEncoder::~OpusTrackEncoder()
 nsresult
 OpusTrackEncoder::Init(int aChannels, int aSamplingRate)
 {
-  // The track must have 1 or 2 channels.
-  if (aChannels <= 0 || aChannels > MAX_CHANNELS) {
-    LOG("[Opus] Fail to create the AudioTrackEncoder! The input has"
-        " %d channel(s), but expects no more than %d.", aChannels, MAX_CHANNELS);
-    return NS_ERROR_INVALID_ARG;
-  }
-
   // This monitor is used to wake up other methods that are waiting for encoder
   // to be completely initialized.
   ReentrantMonitorAutoEnter mon(mReentrantMonitor);
-  mChannels = aChannels;
+  // This version of encoder API only support 1 or 2 channels,
+  // So set the mChannels less or equal 2 and
+  // let InterleaveTrackData downmix pcm data.
+  mChannels = aChannels > 2 ? 2 : aChannels;
 
+  if (aChannels <= 0) {
+    return NS_ERROR_FAILURE;
+  }
   // The granule position is required to be incremented at a rate of 48KHz, and
   // it is simply calculated as |granulepos = samples * (48000/source_rate)|,
   // that is, the source sampling rate must divide 48000 evenly.

content/media/encoder/TrackEncoder.h

@@ -141,8 +141,10 @@ protected:
                            uint32_t aOutputChannels, AudioDataValue* aOutput);
 
   /**
-   * The number of channels in the first valid audio chunk, and is being used
-   * to initialize the audio encoder.
+   * The number of channels are used for processing PCM data in the audio encoder.
+   * This value comes from the first valid audio chunk. If encoder can't support
+   * the channels in the chunk, downmix PCM stream can be performed.
+   * This value also be used to initialize the audio encoder.
    */
   int mChannels;
   int mSamplingRate;

content/media/ogg/OggWriter.cpp

@@ -169,6 +169,7 @@ OggWriter::GetContainerData(nsTArray<nsTArray<uint8_t> >* aOutputBufs,
 nsresult
 OggWriter::SetMetadata(TrackMetadataBase* aMetadata)
 {
+  MOZ_ASSERT(aMetadata);
   if (aMetadata->GetKind() != TrackMetadataBase::METADATA_OPUS) {
     LOG("wrong meta data type!");
     return NS_ERROR_FAILURE;