webrtc/media/engine/videoencodersoftwarefallbackwrapper.h

/*
 *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef WEBRTC_MEDIA_ENGINE_VIDEOENCODERSOFTWAREFALLBACKWRAPPER_H_
#define WEBRTC_MEDIA_ENGINE_VIDEOENCODERSOFTWAREFALLBACKWRAPPER_H_

#include <memory>
#include <string>
#include <vector>

#include "webrtc/api/video_codecs/video_encoder.h"
#include "webrtc/media/base/codec.h"

namespace webrtc {

// Class used to wrap external VideoEncoders to provide a fallback option on
// software encoding when a hardware encoder fails to encode a stream due to
// hardware restrictions, such as max resolution.
class VideoEncoderSoftwareFallbackWrapper : public VideoEncoder {
 public:
  VideoEncoderSoftwareFallbackWrapper(const cricket::VideoCodec& codec,
                                      webrtc::VideoEncoder* encoder);

  int32_t InitEncode(const VideoCodec* codec_settings,
                     int32_t number_of_cores,
                     size_t max_payload_size) override;

  int32_t RegisterEncodeCompleteCallback(
      EncodedImageCallback* callback) override;

  int32_t Release() override;
  int32_t Encode(const VideoFrame& frame,
                 const CodecSpecificInfo* codec_specific_info,
                 const std::vector<FrameType>* frame_types) override;
  int32_t SetChannelParameters(uint32_t packet_loss, int64_t rtt) override;
  int32_t SetRateAllocation(const BitrateAllocation& bitrate_allocation,
                            uint32_t framerate) override;
  bool SupportsNativeHandle() const override;
  ScalingSettings GetScalingSettings() const override;
  const char *ImplementationName() const override;

 private:
  bool InitFallbackEncoder();

  // Settings used in the last InitEncode call and used if a dynamic fallback to
  // software is required.
  VideoCodec codec_settings_;
  int32_t number_of_cores_;
  size_t max_payload_size_;

  // The last bitrate/framerate set, and a flag for noting they are set.
  bool rates_set_;
  BitrateAllocation bitrate_allocation_;
  uint32_t framerate_;

  // The last channel parameters set, and a flag for noting they are set.
  bool channel_parameters_set_;
  uint32_t packet_loss_;
  int64_t rtt_;

  const cricket::VideoCodec codec_;
  webrtc::VideoEncoder* const encoder_;

  std::unique_ptr<webrtc::VideoEncoder> fallback_encoder_;
  std::string fallback_implementation_name_;
  EncodedImageCallback* callback_;
};

}  // namespace webrtc

#endif  // WEBRTC_MEDIA_ENGINE_VIDEOENCODERSOFTWAREFALLBACKWRAPPER_H_