gecko/dom/media/fmp4/gonk/GonkMediaDataDecoder.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#if !defined(GonkMediaDataDecoder_h_)
#define GonkMediaDataDecoder_h_
#include "mp4_demuxer/mp4_demuxer.h"
#include "mozilla/RefPtr.h"
#include "MP4Reader.h"

namespace android {
class MediaCodecProxy;
} // namespace android

namespace mozilla {

// Manage the data flow from inputting encoded data and outputting decode data.
class GonkDecoderManager {
public:
  GonkDecoderManager(MediaTaskQueue* aTaskQueue);

  virtual ~GonkDecoderManager() {}

  // Creates and initializs the GonkDecoder.
  // Returns nullptr on failure.
  virtual android::sp<android::MediaCodecProxy> Init(MediaDataDecoderCallback* aCallback) = 0;

  // Add samples into OMX decoder or queue them if decoder is out of input buffer.
  virtual nsresult Input(mp4_demuxer::MP4Sample* aSample);

  // Produces decoded output, it blocks until output can be produced or a timeout
  // is expired or until EOS. Returns NS_OK on success, or NS_ERROR_NOT_AVAILABLE
  // if there's not enough data to produce more output. If this returns a failure
  // code other than NS_ERROR_NOT_AVAILABLE, an error will be reported to the
  // MP4Reader.
  // The overrided class should follow the same behaviour.
  virtual nsresult Output(int64_t aStreamOffset,
                          nsRefPtr<MediaData>& aOutput) = 0;

  // Flush the queued sample.
  // It this function is overrided by subclass, this functino should be called
  // in the overrided function.
  virtual nsresult Flush();

  virtual void AllocateMediaResources() {}

  virtual void ReleaseMediaResources() {}

  // It should be called in MediaTash thread.
  bool HasQueuedSample() {
    MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
    return mQueueSample.Length();
  }

  void ClearQueuedSample() {
    MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
    mQueueSample.Clear();
  }

protected:
  // It performs special operation to MP4 sample, the real action is depended on
  // the codec type.
  virtual bool PerformFormatSpecificProcess(mp4_demuxer::MP4Sample* aSample) { return true; }

  // It sends MP4Sample to OMX layer. It must be overrided by subclass.
  virtual android::status_t SendSampleToOMX(mp4_demuxer::MP4Sample* aSample) = 0;

  // An queue with the MP4 samples which are waiting to be sent into OMX.
  // If an element is an empty MP4Sample, that menas EOS. There should not
  // any sample be queued after EOS.
  nsTArray<nsAutoPtr<mp4_demuxer::MP4Sample>> mQueueSample;

  RefPtr<MediaTaskQueue> mTaskQueue;
};

// Samples are decoded using the GonkDecoder (MediaCodec)
// created by the GonkDecoderManager. This class implements
// the higher-level logic that drives mapping the Gonk to the async
// MediaDataDecoder interface. The specifics of decoding the exact stream
// type are handled by GonkDecoderManager and the GonkDecoder it creates.
class GonkMediaDataDecoder : public MediaDataDecoder {
public:
  GonkMediaDataDecoder(GonkDecoderManager* aDecoderManager,
                       FlushableMediaTaskQueue* aTaskQueue,
                       MediaDataDecoderCallback* aCallback);

  ~GonkMediaDataDecoder();

  virtual nsresult Init() override;

  virtual nsresult Input(mp4_demuxer::MP4Sample* aSample);

  virtual nsresult Flush() override;

  virtual nsresult Drain() override;

  virtual nsresult Shutdown() override;

  virtual bool IsWaitingMediaResources() override;

  virtual bool IsDormantNeeded() { return true;}

  virtual void AllocateMediaResources() override;

  virtual void ReleaseMediaResources() override;

private:

  // Called on the task queue. Inserts the sample into the decoder, and
  // extracts output if available, if aSample is null, it means there is
  // no data from source, it will notify the decoder EOS and flush all the
  // decoded frames.
  void ProcessDecode(mp4_demuxer::MP4Sample* aSample);

  // Called on the task queue. Extracts output if available, and delivers
  // it to the reader. Called after ProcessDecode() and ProcessDrain().
  void ProcessOutput();

  // Called on the task queue. Orders the Gonk to drain, and then extracts
  // all available output.
  void ProcessDrain();

  RefPtr<FlushableMediaTaskQueue> mTaskQueue;
  MediaDataDecoderCallback* mCallback;

  android::sp<android::MediaCodecProxy> mDecoder;
  nsAutoPtr<GonkDecoderManager> mManager;

  // The last offset into the media resource that was passed into Input().
  // This is used to approximate the decoder's position in the media resource.
  int64_t mLastStreamOffset;
  // Set it ture when there is no input data
  bool mSignaledEOS;
  // Set if there is no more output data from decoder
  bool mDrainComplete;
};

} // namespace mozilla

#endif // GonkMediaDataDecoder_h_