Cast: Adding support for GPU accelerated encode

media/cast/video_sender/video_encoder.h

 // Copyright 2013 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.
 
 #ifndef MEDIA_CAST_VIDEO_SENDER_VIDEO_ENCODER_H_
 #define MEDIA_CAST_VIDEO_SENDER_VIDEO_ENCODER_H_
 
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
-#include "base/message_loop/message_loop.h"
+#include "base/time/time.h"
+#include "media/base/video_frame.h"
 #include "media/cast/cast_config.h"
 #include "media/cast/cast_environment.h"
-#include "media/cast/video_sender/codecs/vp8/vp8_encoder.h"
-
-namespace media {
-class VideoFrame;
-}
 
 namespace media {
 namespace cast {
 
-// This object is called external from the main cast thread and internally from
-// the video encoder thread.
-class VideoEncoder : public VideoEncoderController {
+// All these functions are called from the main cast thread.
+class VideoEncoder {
  public:
   typedef base::Callback<void(scoped_ptr<EncodedVideoFrame>,
                               const base::TimeTicks&)> FrameEncodedCallback;
 
-  VideoEncoder(scoped_refptr<CastEnvironment> cast_environment,
-               const VideoSenderConfig& video_config,
-               uint8 max_unacked_frames);
+  virtual ~VideoEncoder() {}
 
-  virtual ~VideoEncoder();
-
-  // Called from the main cast thread. This function post the encode task to the
-  // video encoder thread;
   // The video_frame must be valid until the closure callback is called.
   // The closure callback is called from the video encoder thread as soon as
   // the encoder is done with the frame; it does not mean that the encoded frame
   // has been sent out.
   // Once the encoded frame is ready the frame_encoded_callback is called.
-  bool EncodeVideoFrame(const scoped_refptr<media::VideoFrame>& video_frame,
-                        const base::TimeTicks& capture_time,
-                        const FrameEncodedCallback& frame_encoded_callback);
-
- protected:
-  struct CodecDynamicConfig {
-    bool key_frame_requested;
-    uint32 latest_frame_id_to_reference;
-    int bit_rate;
-  };
-
-  // The actual encode, called from the video encoder thread.
-  void EncodeVideoFrameEncoderThread(
+  virtual bool EncodeVideoFrame(
       const scoped_refptr<media::VideoFrame>& video_frame,
       const base::TimeTicks& capture_time,
-      const CodecDynamicConfig& dynamic_config,
-      const FrameEncodedCallback& frame_encoded_callback);
+      const FrameEncodedCallback& frame_encoded_callback) = 0;
 
-  // The following functions are called from the main cast thread.
-  virtual void SetBitRate(int new_bit_rate) OVERRIDE;
-  virtual void SkipNextFrame(bool skip_next_frame) OVERRIDE;
-  virtual void GenerateKeyFrame() OVERRIDE;
-  virtual void LatestFrameIdToReference(uint32 frame_id) OVERRIDE;
-  virtual int NumberOfSkippedFrames() const OVERRIDE;
+  // Inform the encoder about the new target bit rate.
+  virtual void SetBitRate(int new_bit_rate) = 0;
 
- private:
-  friend class base::RefCountedThreadSafe<VideoEncoder>;
+  // Inform the encoder to not encode the next frame.
+  // Note: this setting is sticky and should last until called with false.
+  virtual void SkipNextFrame(bool skip_next_frame) = 0;
 
-  const VideoSenderConfig video_config_;
-  scoped_refptr<CastEnvironment> cast_environment_;
-  scoped_ptr<Vp8Encoder> vp8_encoder_;
-  CodecDynamicConfig dynamic_config_;
-  bool skip_next_frame_;
-  int skip_count_;
+  // Inform the encoder to encode the next frame as a key frame.
+  virtual void GenerateKeyFrame() = 0;
 
-  DISALLOW_COPY_AND_ASSIGN(VideoEncoder);
+  // Inform the encoder to only reference frames older or equal to frame_id;
+  virtual void LatestFrameIdToReference(uint32 frame_id) = 0;
+
+  // Query the codec about how many frames it has skipped due to slow ACK.
+  virtual int NumberOfSkippedFrames() const = 0;
 };
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_VIDEO_SENDER_VIDEO_ENCODER_H_
+