content/renderer/media/rtc_video_decoder.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_H_
   6 #define CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_H_
   7
   8 #include <deque>
   9 #include <list>
  10 #include <map>
  11 #include <set>
  12 #include <utility>
  13
  14 #include "base/basictypes.h"
  15 #include "base/gtest_prod_util.h"
  16 #include "base/memory/weak_ptr.h"
  17 #include "base/synchronization/lock.h"
  18 #include "base/threading/thread.h"
  19 #include "content/common/content_export.h"
  20 #include "media/base/bitstream_buffer.h"
  21 #include "media/base/video_decoder.h"
  22 #include "media/video/picture.h"
  23 #include "media/video/video_decode_accelerator.h"
  24 #include "third_party/webrtc/modules/video_coding/codecs/interface/video_codec_interface.h"
  25
  26 namespace base {
  27 class WaitableEvent;
  28 class MessageLoopProxy;
  29 };
  30
  31 namespace media {
  32 class DecoderBuffer;
  33 class GpuVideoAcceleratorFactories;
  34 }
  35
  36 namespace content {
  37
  38 // This class uses hardware accelerated video decoder to decode video for
  39 // WebRTC. |vda_message_loop_| is the message loop proxy of the media thread,
  40 // which VDA::Client methods run on. webrtc::VideoDecoder methods run on WebRTC
  41 // DecodingThread or Chrome_libJingle_WorkerThread, which are trampolined to
  42 // |vda_message_loop_|. Decode() is non-blocking and queues the buffers. Decoded
  43 // frames are delivered to WebRTC on |vda_message_loop_|.
  44 class CONTENT_EXPORT RTCVideoDecoder
  45     : NON_EXPORTED_BASE(public webrtc::VideoDecoder),
  46       public media::VideoDecodeAccelerator::Client {
  47  public:
  48   virtual ~RTCVideoDecoder();
  49
  50   // Creates a RTCVideoDecoder. Returns NULL if failed. The video decoder will
  51   // run on the message loop of |factories|.
  52   static scoped_ptr<RTCVideoDecoder> Create(
  53       webrtc::VideoCodecType type,
  54       const scoped_refptr<media::GpuVideoAcceleratorFactories>& factories);
  55
  56   // webrtc::VideoDecoder implementation.
  57   // Called on WebRTC DecodingThread.
  58   virtual int32_t InitDecode(const webrtc::VideoCodec* codecSettings,
  59                              int32_t numberOfCores) OVERRIDE;
  60   // Called on WebRTC DecodingThread.
  61   virtual int32_t Decode(
  62       const webrtc::EncodedImage& inputImage,
  63       bool missingFrames,
  64       const webrtc::RTPFragmentationHeader* fragmentation,
  65       const webrtc::CodecSpecificInfo* codecSpecificInfo = NULL,
  66       int64_t renderTimeMs = -1) OVERRIDE;
  67   // Called on WebRTC DecodingThread.
  68   virtual int32_t RegisterDecodeCompleteCallback(
  69       webrtc::DecodedImageCallback* callback) OVERRIDE;
  70   // Called on Chrome_libJingle_WorkerThread. The child thread is blocked while
  71   // this runs.
  72   virtual int32_t Release() OVERRIDE;
  73   // Called on Chrome_libJingle_WorkerThread. The child thread is blocked while
  74   // this runs.
  75   virtual int32_t Reset() OVERRIDE;
  76
  77   // VideoDecodeAccelerator::Client implementation.
  78   virtual void ProvidePictureBuffers(uint32 count,
  79                                      const gfx::Size& size,
  80                                      uint32 texture_target) OVERRIDE;
  81   virtual void DismissPictureBuffer(int32 id) OVERRIDE;
  82   virtual void PictureReady(const media::Picture& picture) OVERRIDE;
  83   virtual void NotifyEndOfBitstreamBuffer(int32 id) OVERRIDE;
  84   virtual void NotifyFlushDone() OVERRIDE;
  85   virtual void NotifyResetDone() OVERRIDE;
  86   virtual void NotifyError(media::VideoDecodeAccelerator::Error error) OVERRIDE;
  87
  88  private:
  89   class SHMBuffer;
  90   // Metadata of a bitstream buffer.
  91   struct BufferData {
  92     BufferData(int32 bitstream_buffer_id,
  93                uint32_t timestamp,
  94                int width,
  95                int height,
  96                size_t size);
  97     BufferData();
  98     ~BufferData();
  99     int32 bitstream_buffer_id;
 100     uint32_t timestamp;  // in 90KHz
 101     uint32_t width;
 102     uint32_t height;
 103     size_t size;  // buffer size
 104   };
 105
 106   FRIEND_TEST_ALL_PREFIXES(RTCVideoDecoderTest, IsBufferAfterReset);
 107   FRIEND_TEST_ALL_PREFIXES(RTCVideoDecoderTest, IsFirstBufferAfterReset);
 108
 109   RTCVideoDecoder(
 110       const scoped_refptr<media::GpuVideoAcceleratorFactories>& factories);
 111
 112   // Requests a buffer to be decoded by VDA.
 113   void RequestBufferDecode();
 114
 115   bool CanMoreDecodeWorkBeDone();
 116
 117   // Returns true if bitstream buffer id |id_buffer| comes after |id_reset|.
 118   // This handles the wraparound.
 119   bool IsBufferAfterReset(int32 id_buffer, int32 id_reset);
 120
 121   // Returns true if bitstream buffer |id_buffer| is the first buffer after
 122   // |id_reset|.
 123   bool IsFirstBufferAfterReset(int32 id_buffer, int32 id_reset);
 124
 125   // Saves a WebRTC buffer in |decode_buffers_| for decode.
 126   void SaveToDecodeBuffers_Locked(const webrtc::EncodedImage& input_image,
 127                                   scoped_ptr<SHMBuffer> shm_buffer,
 128                                   const BufferData& buffer_data);
 129
 130   // Saves a WebRTC buffer in |pending_buffers_| waiting for SHM available.
 131   // Returns true on success.
 132   bool SaveToPendingBuffers_Locked(const webrtc::EncodedImage& input_image,
 133                                    const BufferData& buffer_data);
 134
 135   // Gets SHM and moves pending buffers to decode buffers.
 136   void MovePendingBuffersToDecodeBuffers();
 137
 138   scoped_refptr<media::VideoFrame> CreateVideoFrame(
 139       const media::Picture& picture,
 140       const media::PictureBuffer& pb,
 141       uint32_t timestamp,
 142       uint32_t width,
 143       uint32_t height,
 144       size_t size);
 145
 146   // Resets VDA.
 147   void ResetInternal();
 148
 149   // Static method is to allow it to run even after RVD is deleted.
 150   static void ReleaseMailbox(
 151       base::WeakPtr<RTCVideoDecoder> decoder,
 152       const scoped_refptr<media::GpuVideoAcceleratorFactories>& factories,
 153       int64 picture_buffer_id,
 154       uint32 texture_id,
 155       const std::vector<uint32>& release_sync_points);
 156   // Tells VDA that a picture buffer can be recycled.
 157   void ReusePictureBuffer(int64 picture_buffer_id);
 158
 159   // Create |vda_| on |vda_loop_proxy_|.
 160   void CreateVDA(media::VideoCodecProfile profile, base::WaitableEvent* waiter);
 161
 162   void DestroyTextures();
 163   void DestroyVDA();
 164
 165   // Gets a shared-memory segment of at least |min_size| bytes from
 166   // |available_shm_segments_|. Returns NULL if there is no buffer or the
 167   // buffer is not big enough.
 168   scoped_ptr<SHMBuffer> GetSHM_Locked(size_t min_size);
 169
 170   // Returns a shared-memory segment to the available pool.
 171   void PutSHM_Locked(scoped_ptr<SHMBuffer> shm_buffer);
 172
 173   // Allocates |number| shared memory of at least |min_size| bytes.
 174   void CreateSHM(int number, size_t min_size);
 175
 176   // Stores the buffer metadata to |input_buffer_data_|.
 177   void RecordBufferData(const BufferData& buffer_data);
 178   // Gets the buffer metadata from |input_buffer_data_|.
 179   void GetBufferData(int32 bitstream_buffer_id,
 180                      uint32_t* timestamp,
 181                      uint32_t* width,
 182                      uint32_t* height,
 183                      size_t* size);
 184
 185   // Records the result of InitDecode to UMA and returns |status|.
 186   int32_t RecordInitDecodeUMA(int32_t status);
 187
 188   // Assert the contract that this class is operated on the right thread.
 189   void DCheckGpuVideoAcceleratorFactoriesTaskRunnerIsCurrent() const;
 190
 191   enum State {
 192     UNINITIALIZED,  // The decoder has not initialized.
 193     INITIALIZED,    // The decoder has initialized.
 194     RESETTING,      // The decoder is being reset.
 195     DECODE_ERROR,   // Decoding error happened.
 196   };
 197
 198   static const int32 ID_LAST;     // maximum bitstream buffer id
 199   static const int32 ID_HALF;     // half of the maximum bitstream buffer id
 200   static const int32 ID_INVALID;  // indicates Reset or Release never occurred
 201
 202   // The hardware video decoder.
 203   scoped_ptr<media::VideoDecodeAccelerator> vda_;
 204
 205   // The size of the incoming video frames.
 206   gfx::Size frame_size_;
 207
 208   scoped_refptr<media::GpuVideoAcceleratorFactories> factories_;
 209
 210   // The texture target used for decoded pictures.
 211   uint32 decoder_texture_target_;
 212
 213   // Metadata of the buffers that have been sent for decode.
 214   std::list<BufferData> input_buffer_data_;
 215
 216   // A map from bitstream buffer IDs to bitstream buffers that are being
 217   // processed by VDA. The map owns SHM buffers.
 218   std::map<int32, SHMBuffer*> bitstream_buffers_in_decoder_;
 219
 220   // A map from picture buffer IDs to texture-backed picture buffers.
 221   std::map<int32, media::PictureBuffer> assigned_picture_buffers_;
 222
 223   // PictureBuffers given to us by VDA via PictureReady, which we sent forward
 224   // as VideoFrames to be rendered via read_cb_, and which will be returned
 225   // to us via ReusePictureBuffer.
 226   typedef std::map<int32 /* picture_buffer_id */, uint32 /* texture_id */>
 227       PictureBufferTextureMap;
 228   PictureBufferTextureMap picture_buffers_at_display_;
 229
 230   // The id that will be given to the next picture buffer.
 231   int32 next_picture_buffer_id_;
 232
 233   // Protects |state_|, |decode_complete_callback_| , |num_shm_buffers_|,
 234   // |available_shm_segments_|, |pending_buffers_|, |decode_buffers_|,
 235   // |next_bitstream_buffer_id_| and |reset_bitstream_buffer_id_|.
 236   base::Lock lock_;
 237
 238   // The state of RTCVideoDecoder. Guarded by |lock_|.
 239   State state_;
 240
 241   // Guarded by |lock_|.
 242   webrtc::DecodedImageCallback* decode_complete_callback_;
 243
 244   // Total number of allocated SHM buffers. Guarded by |lock_|.
 245   int num_shm_buffers_;
 246
 247   // Shared-memory buffer pool.  Since allocating SHM segments requires a
 248   // round-trip to the browser process, we keep allocation out of the
 249   // steady-state of the decoder. The vector owns SHM buffers. Guarded by
 250   // |lock_|.
 251   std::vector<SHMBuffer*> available_shm_segments_;
 252
 253   // A queue storing WebRTC encoding images (and their metadata) that are
 254   // waiting for the shared memory. Guarded by |lock_|.
 255   std::deque<std::pair<webrtc::EncodedImage, BufferData> > pending_buffers_;
 256
 257   // A queue storing buffers (and their metadata) that will be sent to VDA for
 258   // decode. The queue owns SHM buffers. Guarded by |lock_|.
 259   std::deque<std::pair<SHMBuffer*, BufferData> > decode_buffers_;
 260
 261   // The id that will be given to the next bitstream buffer. Guarded by |lock_|.
 262   int32 next_bitstream_buffer_id_;
 263
 264   // A buffer that has an id less than this should be dropped because Reset or
 265   // Release has been called. Guarded by |lock_|.
 266   int32 reset_bitstream_buffer_id_;
 267
 268   // Must be destroyed, or invalidated, on |vda_loop_proxy_|
 269   // NOTE: Weak pointers must be invalidated before all other member variables.
 270   base::WeakPtrFactory<RTCVideoDecoder> weak_factory_;
 271
 272   DISALLOW_COPY_AND_ASSIGN(RTCVideoDecoder);
 273 };
 274
 275 }  // namespace content
 276
 277 #endif  // CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_H_