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                size_t size);
  95     BufferData();
  96     ~BufferData();
  97     int32 bitstream_buffer_id;
  98     uint32_t timestamp;  // in 90KHz
  99     size_t size;  // buffer size
 100   };
 101
 102   FRIEND_TEST_ALL_PREFIXES(RTCVideoDecoderTest, IsBufferAfterReset);
 103   FRIEND_TEST_ALL_PREFIXES(RTCVideoDecoderTest, IsFirstBufferAfterReset);
 104
 105   RTCVideoDecoder(
 106       webrtc::VideoCodecType type,
 107       const scoped_refptr<media::GpuVideoAcceleratorFactories>& factories);
 108
 109   // Requests a buffer to be decoded by VDA.
 110   void RequestBufferDecode();
 111
 112   bool CanMoreDecodeWorkBeDone();
 113
 114   // Returns true if bitstream buffer id |id_buffer| comes after |id_reset|.
 115   // This handles the wraparound.
 116   bool IsBufferAfterReset(int32 id_buffer, int32 id_reset);
 117
 118   // Returns true if bitstream buffer |id_buffer| is the first buffer after
 119   // |id_reset|.
 120   bool IsFirstBufferAfterReset(int32 id_buffer, int32 id_reset);
 121
 122   // Saves a WebRTC buffer in |decode_buffers_| for decode.
 123   void SaveToDecodeBuffers_Locked(const webrtc::EncodedImage& input_image,
 124                                   scoped_ptr<SHMBuffer> shm_buffer,
 125                                   const BufferData& buffer_data);
 126
 127   // Saves a WebRTC buffer in |pending_buffers_| waiting for SHM available.
 128   // Returns true on success.
 129   bool SaveToPendingBuffers_Locked(const webrtc::EncodedImage& input_image,
 130                                    const BufferData& buffer_data);
 131
 132   // Gets SHM and moves pending buffers to decode buffers.
 133   void MovePendingBuffersToDecodeBuffers();
 134
 135   scoped_refptr<media::VideoFrame> CreateVideoFrame(
 136       const media::Picture& picture,
 137       const media::PictureBuffer& pb,
 138       uint32_t timestamp);
 139
 140   // Resets VDA.
 141   void ResetInternal();
 142
 143   // Static method is to allow it to run even after RVD is deleted.
 144   static void ReleaseMailbox(
 145       base::WeakPtr<RTCVideoDecoder> decoder,
 146       const scoped_refptr<media::GpuVideoAcceleratorFactories>& factories,
 147       int64 picture_buffer_id,
 148       uint32 texture_id,
 149       uint32 release_sync_point);
 150   // Tells VDA that a picture buffer can be recycled.
 151   void ReusePictureBuffer(int64 picture_buffer_id);
 152
 153   // Create |vda_| on |vda_loop_proxy_|.
 154   void CreateVDA(media::VideoCodecProfile profile, base::WaitableEvent* waiter);
 155
 156   void DestroyTextures();
 157   void DestroyVDA();
 158
 159   // Gets a shared-memory segment of at least |min_size| bytes from
 160   // |available_shm_segments_|. Returns NULL if there is no buffer or the
 161   // buffer is not big enough.
 162   scoped_ptr<SHMBuffer> GetSHM_Locked(size_t min_size);
 163
 164   // Returns a shared-memory segment to the available pool.
 165   void PutSHM_Locked(scoped_ptr<SHMBuffer> shm_buffer);
 166
 167   // Allocates |number| shared memory of at least |min_size| bytes.
 168   void CreateSHM(int number, size_t min_size);
 169
 170   // Stores the buffer metadata to |input_buffer_data_|.
 171   void RecordBufferData(const BufferData& buffer_data);
 172   // Gets the buffer metadata from |input_buffer_data_|.
 173   void GetBufferData(int32 bitstream_buffer_id, uint32_t* timestamp);
 174
 175   // Records the result of InitDecode to UMA and returns |status|.
 176   int32_t RecordInitDecodeUMA(int32_t status);
 177
 178   // Assert the contract that this class is operated on the right thread.
 179   void DCheckGpuVideoAcceleratorFactoriesTaskRunnerIsCurrent() const;
 180
 181   enum State {
 182     UNINITIALIZED,  // The decoder has not initialized.
 183     INITIALIZED,    // The decoder has initialized.
 184     RESETTING,      // The decoder is being reset.
 185     DECODE_ERROR,   // Decoding error happened.
 186   };
 187
 188   static const int32 ID_LAST;     // maximum bitstream buffer id
 189   static const int32 ID_HALF;     // half of the maximum bitstream buffer id
 190   static const int32 ID_INVALID;  // indicates Reset or Release never occurred
 191
 192   // The hardware video decoder.
 193   scoped_ptr<media::VideoDecodeAccelerator> vda_;
 194
 195   // The video codec type, as reported by WebRTC.
 196   const webrtc::VideoCodecType video_codec_type_;
 197
 198   // The size of the incoming video frames.
 199   gfx::Size frame_size_;
 200
 201   scoped_refptr<media::GpuVideoAcceleratorFactories> factories_;
 202
 203   // The texture target used for decoded pictures.
 204   uint32 decoder_texture_target_;
 205
 206   // Metadata of the buffers that have been sent for decode.
 207   std::list<BufferData> input_buffer_data_;
 208
 209   // A map from bitstream buffer IDs to bitstream buffers that are being
 210   // processed by VDA. The map owns SHM buffers.
 211   std::map<int32, SHMBuffer*> bitstream_buffers_in_decoder_;
 212
 213   // A map from picture buffer IDs to texture-backed picture buffers.
 214   std::map<int32, media::PictureBuffer> assigned_picture_buffers_;
 215
 216   // PictureBuffers given to us by VDA via PictureReady, which we sent forward
 217   // as VideoFrames to be rendered via read_cb_, and which will be returned
 218   // to us via ReusePictureBuffer.
 219   typedef std::map<int32 /* picture_buffer_id */, uint32 /* texture_id */>
 220       PictureBufferTextureMap;
 221   PictureBufferTextureMap picture_buffers_at_display_;
 222
 223   // The id that will be given to the next picture buffer.
 224   int32 next_picture_buffer_id_;
 225
 226   // Protects |state_|, |decode_complete_callback_| , |num_shm_buffers_|,
 227   // |available_shm_segments_|, |pending_buffers_|, |decode_buffers_|,
 228   // |next_bitstream_buffer_id_| and |reset_bitstream_buffer_id_|.
 229   base::Lock lock_;
 230
 231   // The state of RTCVideoDecoder. Guarded by |lock_|.
 232   State state_;
 233
 234   // Guarded by |lock_|.
 235   webrtc::DecodedImageCallback* decode_complete_callback_;
 236
 237   // Total number of allocated SHM buffers. Guarded by |lock_|.
 238   int num_shm_buffers_;
 239
 240   // Shared-memory buffer pool.  Since allocating SHM segments requires a
 241   // round-trip to the browser process, we keep allocation out of the
 242   // steady-state of the decoder. The vector owns SHM buffers. Guarded by
 243   // |lock_|.
 244   std::vector<SHMBuffer*> available_shm_segments_;
 245
 246   // A queue storing WebRTC encoding images (and their metadata) that are
 247   // waiting for the shared memory. Guarded by |lock_|.
 248   std::deque<std::pair<webrtc::EncodedImage, BufferData> > pending_buffers_;
 249
 250   // A queue storing buffers (and their metadata) that will be sent to VDA for
 251   // decode. The queue owns SHM buffers. Guarded by |lock_|.
 252   std::deque<std::pair<SHMBuffer*, BufferData> > decode_buffers_;
 253
 254   // The id that will be given to the next bitstream buffer. Guarded by |lock_|.
 255   int32 next_bitstream_buffer_id_;
 256
 257   // A buffer that has an id less than this should be dropped because Reset or
 258   // Release has been called. Guarded by |lock_|.
 259   int32 reset_bitstream_buffer_id_;
 260
 261   // Must be destroyed, or invalidated, on |vda_loop_proxy_|
 262   // NOTE: Weak pointers must be invalidated before all other member variables.
 263   base::WeakPtrFactory<RTCVideoDecoder> weak_factory_;
 264
 265   DISALLOW_COPY_AND_ASSIGN(RTCVideoDecoder);
 266 };
 267
 268 }  // namespace content
 269
 270 #endif  // CONTENT_RENDERER_MEDIA_RTC_VIDEO_DECODER_H_