| // Copyright 2017 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef MEDIA_FILTERS_OFFLOADING_VIDEO_DECODER_H_ |
| #define MEDIA_FILTERS_OFFLOADING_VIDEO_DECODER_H_ |
| |
| #include "base/callback_forward.h" |
| #include "base/macros.h" |
| #include "base/memory/weak_ptr.h" |
| #include "base/threading/thread_checker.h" |
| #include "media/base/video_codecs.h" |
| #include "media/base/video_decoder.h" |
| #include "media/base/video_decoder_config.h" |
| |
| namespace base { |
| class SequencedTaskRunner; |
| } // namespace base |
| |
| namespace media { |
| |
| class MEDIA_EXPORT OffloadableVideoDecoder : public VideoDecoder { |
| public: |
| ~OffloadableVideoDecoder() override {} |
| |
| // Called by the OffloadingVideoDecoder when closing the decoder and switching |
| // task runners. Will be called on the task runner that Initialize() was |
| // called on. Upon completion of this method implementing decoders must be |
| // ready to be Initialized() on another thread. |
| virtual void Detach() = 0; |
| }; |
| |
| // Wrapper for OffloadableVideoDecoder implementations that runs the wrapped |
| // decoder on a task pool other than the caller's thread. |
| // |
| // Optionally decoders which are aware of the wrapping may choose to not rebind |
| // callbacks to the offloaded thread since they will already be bound by the |
| // OffloadingVideoDecoder; this simply avoids extra hops for completed tasks. |
| class MEDIA_EXPORT OffloadingVideoDecoder : public VideoDecoder { |
| public: |
| // Offloads |decoder| for VideoDecoderConfigs provided to Initialize() using |
| // |supported_codecs| with a coded width >= |min_offloading_width|. |
| // |
| // E.g. if a width of 1024 is specified, and VideoDecoderConfig has a coded |
| // size of 1280x720 we will use offloading. Conversely if the width was |
| // 640x480, we would not use offloading. |
| OffloadingVideoDecoder(int min_offloading_width, |
| std::vector<VideoCodec> supported_codecs, |
| std::unique_ptr<OffloadableVideoDecoder> decoder); |
| ~OffloadingVideoDecoder() override; |
| |
| // VideoDecoder implementation. |
| std::string GetDisplayName() const override; |
| void Initialize(const VideoDecoderConfig& config, |
| bool low_delay, |
| CdmContext* cdm_context, |
| const InitCB& init_cb, |
| const OutputCB& output_cb) override; |
| void Decode(const scoped_refptr<DecoderBuffer>& buffer, |
| const DecodeCB& decode_cb) override; |
| void Reset(const base::Closure& reset_cb) override; |
| |
| private: |
| // VideoDecoderConfigs given to Initialize() with a coded size that has width |
| // greater than or equal to this value will be offloaded. |
| const int min_offloading_width_; |
| |
| // Codecs supported for offloading. |
| const std::vector<VideoCodec> supported_codecs_; |
| |
| // Indicates if Initialize() has been called. |
| bool initialized_ = false; |
| |
| THREAD_CHECKER(thread_checker_); |
| |
| // The decoder which will be offloaded. |
| std::unique_ptr<OffloadableVideoDecoder> decoder_; |
| |
| // High resolution decodes may block the media thread for too long, in such |
| // cases offload the decoding to a task pool. |
| scoped_refptr<base::SequencedTaskRunner> offload_task_runner_; |
| |
| // NOTE: Weak pointers must be invalidated before all other member variables. |
| base::WeakPtrFactory<OffloadingVideoDecoder> weak_factory_; |
| |
| DISALLOW_COPY_AND_ASSIGN(OffloadingVideoDecoder); |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_FILTERS_OFFLOADING_VIDEO_DECODER_H_ |