media/cast/receiver/video_decoder.h

   1 // Copyright 2014 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 MEDIA_CAST_RECEIVER_VIDEO_DECODER_H_
   6 #define MEDIA_CAST_RECEIVER_VIDEO_DECODER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "media/base/video_frame.h"
  12 #include "media/cast/cast_config.h"
  13 #include "media/cast/net/cast_transport_config.h"
  14
  15 namespace media {
  16 namespace cast {
  17
  18 class CastEnvironment;
  19
  20 class VideoDecoder {
  21  public:
  22   // Callback passed to DecodeFrame, to deliver a decoded video frame from the
  23   // decoder.  |frame| can be NULL when errors occur.  |is_continuous| is
  24   // normally true, but will be false if the decoder has detected a frame skip
  25   // since the last decode operation; and the client might choose to take steps
  26   // to smooth/interpolate video discontinuities in this case.
  27   typedef base::Callback<void(const scoped_refptr<VideoFrame>& frame,
  28                               bool is_continuous)> DecodeFrameCallback;
  29
  30   VideoDecoder(const scoped_refptr<CastEnvironment>& cast_environment,
  31                Codec codec);
  32   virtual ~VideoDecoder();
  33
  34   // Returns STATUS_VIDEO_INITIALIZED if the decoder was successfully
  35   // constructed from the given FrameReceiverConfig.  If this method returns any
  36   // other value, calls to DecodeFrame() will not succeed.
  37   CastInitializationStatus InitializationResult() const;
  38
  39   // Decode the payload in |encoded_frame| asynchronously.  |callback| will be
  40   // invoked on the CastEnvironment::MAIN thread with the result.
  41   //
  42   // In the normal case, |encoded_frame->frame_id| will be
  43   // monotonically-increasing by 1 for each successive call to this method.
  44   // When it is not, the decoder will assume one or more frames have been
  45   // dropped (e.g., due to packet loss), and will perform recovery actions.
  46   void DecodeFrame(scoped_ptr<EncodedFrame> encoded_frame,
  47                    const DecodeFrameCallback& callback);
  48
  49  private:
  50   class FakeImpl;
  51   class ImplBase;
  52   class Vp8Impl;
  53
  54   const scoped_refptr<CastEnvironment> cast_environment_;
  55   scoped_refptr<ImplBase> impl_;
  56
  57   DISALLOW_COPY_AND_ASSIGN(VideoDecoder);
  58 };
  59
  60 }  // namespace cast
  61 }  // namespace media
  62
  63 #endif  // MEDIA_CAST_RECEIVER_VIDEO_DECODER_H_