gecko-dev/dom/media/omx/MediaCodecProxy.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/. */

#ifndef MEDIA_CODEC_PROXY_H
#define MEDIA_CODEC_PROXY_H

#include <nsString.h>
#include <stagefright/MediaCodec.h>
#include <stagefright/MediaBuffer.h>
#include <utils/threads.h>
#include "MediaResourceHandler.h"

namespace android {
// This class is intended to be a proxy for MediaCodec with codec resource
// management. Basically user can use it like MediaCodec, but need to handle
// the listener when Codec is reserved for Async case. A good example is
// MediaCodecReader.cpp. Another useage is to use configure(), Prepare(),
// Input(), and Output(). It is used in GonkVideoDecoderManager.cpp which
// doesn't need to handle the buffers for codec.
class MediaCodecProxy : public MediaResourceHandler::ResourceListener
{
public:
  /* Codec resource notification listener.
   * All functions are called on the Binder thread.
   */
  struct CodecResourceListener : public virtual RefBase {
    /* The codec resource is reserved and can be granted.
     * The client can allocate the requested resource.
     */
    virtual void codecReserved() = 0;
    /* The codec resource is not reserved any more.
     * The client should release the resource as soon as possible if the
     * resource is still being held.
     */
    virtual void codecCanceled() = 0;
  };

  enum Capability {
    kEmptyCapability        = 0x00000000,
    kCanExposeGraphicBuffer = 0x00000001,
  };

  enum {
    kKeyBufferIndex = 'bfin',
  };

  // Check whether MediaCodec has been allocated.
  bool allocated() const;

  // Static MediaCodec methods
  // Only support MediaCodec::CreateByType()
  static sp<MediaCodecProxy> CreateByType(sp<ALooper> aLooper,
                                          const char *aMime,
                                          bool aEncoder,
                                          bool aAsync=false,
                                          wp<CodecResourceListener> aListener=nullptr);

  // MediaCodec methods
  status_t configure(const sp<AMessage> &aFormat,
                     const sp<Surface> &aNativeWindow,
                     const sp<ICrypto> &aCrypto,
                     uint32_t aFlags);

  status_t start();

  status_t stop();

  status_t release();

  status_t flush();

  status_t queueInputBuffer(size_t aIndex,
                            size_t aOffset,
                            size_t aSize,
                            int64_t aPresentationTimeUs,
                            uint32_t aFlags,
                            AString *aErrorDetailMessage=nullptr);

  status_t queueSecureInputBuffer(size_t aIndex,
                                  size_t aOffset,
                                  const CryptoPlugin::SubSample *aSubSamples,
                                  size_t aNumSubSamples,
                                  const uint8_t aKey[16],
                                  const uint8_t aIV[16],
                                  CryptoPlugin::Mode aMode,
                                  int64_t aPresentationTimeUs,
                                  uint32_t aFlags,
                                  AString *aErrorDetailMessage=nullptr);

  status_t dequeueInputBuffer(size_t *aIndex,
                              int64_t aTimeoutUs=INT64_C(0));

  status_t dequeueOutputBuffer(size_t *aIndex,
                               size_t *aOffset,
                               size_t *aSize,
                               int64_t *aPresentationTimeUs,
                               uint32_t *aFlags,
                               int64_t aTimeoutUs=INT64_C(0));

  status_t renderOutputBufferAndRelease(size_t aIndex);

  status_t releaseOutputBuffer(size_t aIndex);

  status_t signalEndOfInputStream();

  status_t getOutputFormat(sp<AMessage> *aFormat) const;

  status_t getInputBuffers(Vector<sp<ABuffer>> *aBuffers) const;

  status_t getOutputBuffers(Vector<sp<ABuffer>> *aBuffers) const;

  // Notification will be posted once there "is something to do", i.e.
  // an input/output buffer has become available, a format change is
  // pending, an error is pending.
  void requestActivityNotification(const sp<AMessage> &aNotify);

  status_t getOutputGraphicBufferFromIndex(size_t aIndex,
                                           sp<GraphicBuffer> *aGraphicBuffer);

  status_t getCapability(uint32_t *aCapability);

  // Utility functions

  // If aData is null, will notify decoder input EOS
  status_t Input(const uint8_t* aData, uint32_t aDataSize,
                 int64_t aTimestampUsecs, uint64_t flags);
  status_t Output(MediaBuffer** aBuffer, int64_t aTimeoutUs);
  bool Prepare();
  bool IsWaitingResources();
  bool IsDormantNeeded();
  void RequestMediaResources();
  void ReleaseMediaResources();
  // This updates mOutputBuffer when receiving INFO_OUTPUT_BUFFERS_CHANGED event.
  bool UpdateOutputBuffers();

  void ReleaseMediaBuffer(MediaBuffer* abuffer);

protected:
  virtual ~MediaCodecProxy();

  // MediaResourceHandler::EventListener::resourceReserved()
  virtual void resourceReserved();
  // MediaResourceHandler::EventListener::resourceCanceled()
  virtual void resourceCanceled();

private:
  // Forbidden
  MediaCodecProxy() = delete;
  MediaCodecProxy(const MediaCodecProxy &) = delete;
  const MediaCodecProxy &operator=(const MediaCodecProxy &) = delete;

  // Constructor for MediaCodecProxy::CreateByType
  MediaCodecProxy(sp<ALooper> aLooper,
                  const char *aMime,
                  bool aEncoder,
                  bool aAsync,
                  wp<CodecResourceListener> aListener);

  // Request Resource
  bool requestResource();
  // Cancel Resource
  void cancelResource();

  // Allocate Codec Resource
  bool allocateCodec();
  // Release Codec Resource
  void releaseCodec();

  // MediaCodec Parameter
  sp<ALooper> mCodecLooper;
  nsCString mCodecMime;
  bool mCodecEncoder;

  // Codec Resource Notification Listener
  wp<CodecResourceListener> mListener;

  // Media Resource Management
  sp<MediaResourceHandler> mResourceHandler;

  // MediaCodec instance
  mutable RWLock mCodecLock;
  sp<MediaCodec> mCodec;

  //MediaCodec buffers to hold input/output data.
  Vector<sp<ABuffer> > mInputBuffers;
  Vector<sp<ABuffer> > mOutputBuffers;

};

} // namespace android

#endif // MEDIA_CODEC_PROXY_H