blob: 67514f7a1400e1c89ccdf4855da6725a467a6158 [file] [log] [blame]
// Copyright 2019 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 <linux/videodev2.h>
#include <map>
#include <memory>
#include <utility>
#include <vector>
#include "base/callback_forward.h"
#include "base/containers/mru_cache.h"
#include "base/containers/queue.h"
#include "base/memory/scoped_refptr.h"
#include "base/memory/weak_ptr.h"
#include "base/sequence_checker.h"
#include "base/sequenced_task_runner.h"
#include "base/threading/thread.h"
#include "base/time/time.h"
#include "media/base/cdm_context.h"
#include "media/base/supported_video_decoder_config.h"
#include "media/base/video_aspect_ratio.h"
#include "media/base/video_types.h"
#include "media/gpu/chromeos/gpu_buffer_layout.h"
#include "media/gpu/chromeos/video_decoder_pipeline.h"
#include "media/gpu/media_gpu_export.h"
#include "media/gpu/v4l2/v4l2_device.h"
#include "media/gpu/v4l2/v4l2_video_decoder_backend.h"
#include "ui/gfx/geometry/size.h"
namespace media {
class DmabufVideoFramePool;
class MEDIA_GPU_EXPORT V4L2VideoDecoder
: public VideoDecoderMixin,
public V4L2VideoDecoderBackend::Client {
// Create V4L2VideoDecoder instance. The success of the creation doesn't
// ensure V4L2VideoDecoder is available on the device. It will be
// determined in Initialize().
static std::unique_ptr<VideoDecoderMixin> Create(
scoped_refptr<base::SequencedTaskRunner> decoder_task_runner,
base::WeakPtr<VideoDecoderMixin::Client> client);
static SupportedVideoDecoderConfigs GetSupportedConfigs();
// VideoDecoderMixin implementation, VideoDecoder part.
void Initialize(const VideoDecoderConfig& config,
bool low_delay,
CdmContext* cdm_context,
InitCB init_cb,
const OutputCB& output_cb,
const WaitingCB& waiting_cb) override;
void Decode(scoped_refptr<DecoderBuffer> buffer, DecodeCB decode_cb) override;
void Reset(base::OnceClosure reset_cb) override;
bool NeedsBitstreamConversion() const override;
bool CanReadWithoutStalling() const override;
int GetMaxDecodeRequests() const override;
VideoDecoderType GetDecoderType() const override;
bool IsPlatformDecoder() const override;
// VideoDecoderMixin implementation, specific part.
void ApplyResolutionChange() override;
// V4L2VideoDecoderBackend::Client implementation
void OnBackendError() override;
bool IsDecoding() const override;
void InitiateFlush() override;
void CompleteFlush() override;
void ChangeResolution(gfx::Size pic_size,
gfx::Rect visible_rect,
size_t num_output_frames) override;
void OutputFrame(scoped_refptr<VideoFrame> frame,
const gfx::Rect& visible_rect,
base::TimeDelta timestamp) override;
DmabufVideoFramePool* GetVideoFramePool() const override;
friend class V4L2VideoDecoderTest;
V4L2VideoDecoder(scoped_refptr<base::SequencedTaskRunner> decoder_task_runner,
base::WeakPtr<VideoDecoderMixin::Client> client,
scoped_refptr<V4L2Device> device);
~V4L2VideoDecoder() override;
enum class State {
// Initial state. Transitions to |kInitialized| if Initialize() is
// successful,
// |kError| otherwise.
// Transitions to |kDecoding| when an input buffer has arrived that
// allows creation of hardware contexts. |kError| on error.
// Transitions to |kFlushing| when flushing or changing resolution,
// |kError| if any unexpected error occurs.
// Transitions to |kDecoding| when flushing or changing resolution is
// finished. Do not process new input buffer in this state.
// Error state. Cannot transition to other state anymore.
class BitstreamIdGenerator {
BitstreamIdGenerator() { DETACH_FROM_SEQUENCE(sequence_checker_); }
int32_t GetNextBitstreamId() {
next_bitstream_buffer_id_ = (next_bitstream_buffer_id_ + 1) & 0x7FFFFFFF;
return next_bitstream_buffer_id_;
int32_t next_bitstream_buffer_id_ = 0;
// Setup format for input queue.
bool SetupInputFormat(uint32_t input_format_fourcc);
// Setup format for output queue. This function sets output format on output
// queue that is supported by a v4l2 driver, can be allocatable by
// VideoFramePool and can be composited by chrome. This also updates format
// in VideoFramePool. Return true if the setup is successful.
bool SetupOutputFormat(const gfx::Size& size, const gfx::Rect& visible_rect);
// Start streaming V4L2 input and (if |start_output_queue| is true) output
// queues. Attempt to start |device_poll_thread_| after streaming starts.
bool StartStreamV4L2Queue(bool start_output_queue);
// Stop streaming V4L2 output and (if |stop_input_queue| is true) input
// queues. Stop |device_poll_thread_| before stopping streaming.
bool StopStreamV4L2Queue(bool stop_input_queue);
// Try to dequeue input and output buffers from device.
void ServiceDeviceTask(bool event);
// After the pipeline finished flushing frames, reconfigure the resolution
// setting of V4L2 device and the frame pool.
void ContinueChangeResolution(const gfx::Size& pic_size,
const gfx::Rect& visible_rect,
const size_t num_output_frames);
// Change the state and check the state transition is valid.
void SetState(State new_state);
// Continue backend initialization. Decoder will not take a hardware context
// until InitializeBackend() is called.
StatusCode InitializeBackend();
// Pages with multiple V4L2VideoDecoder instances might run out of memory
// (e.g. b/170870476) or crash (e.g. To avoid that and
// while the investigation goes on, limit the maximum number of simultaneous
// decoder instances for now. |num_instances_| tracks the number of
// simultaneous decoders. |can_use_decoder_| is true iff we haven't reached
// the maximum number of instances at the time this decoder is created.
static constexpr int kMaxNumOfInstances = 32;
static base::AtomicRefCount num_instances_;
bool can_use_decoder_ = false;
// The V4L2 backend, i.e. the part of the decoder that sends
// decoding jobs to the kernel.
std::unique_ptr<V4L2VideoDecoderBackend> backend_;
// V4L2 device in use.
scoped_refptr<V4L2Device> device_;
// Callback to change resolution, called after the pipeline is flushed.
base::OnceClosure continue_change_resolution_cb_;
// State of the instance.
State state_ = State::kUninitialized;
// Number of output frames requested to |frame_pool_|.
// The default value is only used at the first time of
// DmabufVideoFramePool::Initialize() during Initialize().
size_t num_output_frames_ = 1;
// Aspect ratio from config to use for output frames.
VideoAspectRatio aspect_ratio_;
// Callbacks passed from Initialize().
OutputCB output_cb_;
// Hold onto profile passed in from Initialize() so that
// it is available for InitializeBackend().
VideoCodecProfile profile_ = VIDEO_CODEC_PROFILE_UNKNOWN;
// V4L2 input and output queue.
scoped_refptr<V4L2Queue> input_queue_;
scoped_refptr<V4L2Queue> output_queue_;
BitstreamIdGenerator bitstream_id_generator_;
// |weak_this_| must be dereferenced and invalidated on
// |decoder_task_runner_|.
base::WeakPtr<V4L2VideoDecoder> weak_this_;
base::WeakPtrFactory<V4L2VideoDecoder> weak_this_factory_;
} // namespace media