blob: 556558e2168146da03cf85ec464a105819c7080a [file] [log] [blame]
// 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.
#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 {
~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 {
// 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;
// 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;
// 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_;
} // namespace media