blob: f3e341e64498fbf87e95b1bd47d17f83dd5bb7e1 [file] [log] [blame]
// Copyright (c) 2012 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.h"
#include "base/macros.h"
#include "base/threading/thread_checker.h"
#include "media/base/demuxer_stream.h"
#include "media/base/video_decoder.h"
#include "media/base/video_decoder_config.h"
#include "media/base/video_frame.h"
#include "media/base/video_frame_pool.h"
struct vpx_codec_ctx;
struct vpx_image;
namespace base {
class SingleThreadTaskRunner;
namespace media {
// Libvpx video decoder wrapper.
// Note: VpxVideoDecoder accepts only YV12A VP8 content or VP9 content. This is
// done to avoid usurping FFmpeg for all VP8 decoding, because the FFmpeg VP8
// decoder is faster than the libvpx VP8 decoder.
// Alpha channel, if any, is sent in the DecoderBuffer's side_data() as a frame
// on its own of which the Y channel is taken [1].
// [1]
class MEDIA_EXPORT VpxVideoDecoder : public VideoDecoder {
~VpxVideoDecoder() 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& closure) override;
enum DecoderState {
// Return values for decoding alpha plane.
enum AlphaDecodeStatus {
kAlphaPlaneProcessed, // Alpha plane (if found) was decoded successfully.
kNoAlphaPlaneData, // Alpha plane was found, but decoder did not return any
// data.
kAlphaPlaneError // Fatal error occured when trying to decode alpha plane.
// Handles (re-)initializing the decoder with a (new) config.
// Returns true when initialization was successful.
bool ConfigureDecoder(const VideoDecoderConfig& config);
void CloseDecoder();
// Helper method for decoding buffers either on the offload thread or directly
// on the media thread. |bound_decode_cb| must be bound to the thread that
// called Decode().
void DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer,
const DecodeCB& bound_decode_cb);
// Try to decode |buffer| into |video_frame|. Return true if all decoding
// succeeded. Note that decoding can succeed and still |video_frame| be
// nullptr if there has been a partial decoding.
bool VpxDecode(const scoped_refptr<DecoderBuffer>& buffer,
scoped_refptr<VideoFrame>* video_frame);
bool CopyVpxImageToVideoFrame(const struct vpx_image* vpx_image,
const struct vpx_image* vpx_image_alpha,
scoped_refptr<VideoFrame>* video_frame);
AlphaDecodeStatus DecodeAlphaPlane(
const struct vpx_image* vpx_image,
const struct vpx_image** vpx_image_alpha,
const scoped_refptr<DecoderBuffer>& buffer);
base::ThreadChecker thread_checker_;
// |state_| must only be read and written to on |offload_task_runner_| if it
// is non-null and there are outstanding tasks on the offload thread.
DecoderState state_;
OutputCB output_cb_;
VideoDecoderConfig config_;
vpx_codec_ctx* vpx_codec_;
vpx_codec_ctx* vpx_codec_alpha_;
// |memory_pool_| is a single-threaded memory pool used for VP9 decoding
// with no alpha. |frame_pool_| is used for all other cases.
class MemoryPool;
scoped_refptr<MemoryPool> memory_pool_;
// High resolution vp9 may block the media thread for too long, in such cases
// we share a per-process thread to avoid overly long blocks.
scoped_refptr<base::SingleThreadTaskRunner> offload_task_runner_;
VideoFramePool frame_pool_;
} // namespace media