Cast: Refactoring Cast API's

media/cast/cast_sender.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.
 //
-// This is the main interface for the cast sender. All configuration are done
-// at creation.
+// This is the main interface for the cast sender.
 //
-// The FrameInput and PacketReciever interfaces should normally be accessed from
-// the IO thread. However they are allowed to be called from any thread.
+// The AudioFrameInput, VideoFrameInput and PacketReciever interfaces should
+// be accessed from the IO thread. However they may be called from any thread.

[Alpha Left Google, 2014/02/18 22:28:13]

media/cast has no concept of an "IO" thread. This should be the Cast main
thread.

[mikhal1, 2014/03/05 21:44:05]

Done.

 
 #ifndef MEDIA_CAST_CAST_SENDER_H_
 #define MEDIA_CAST_CAST_SENDER_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/tick_clock.h"
 #include "base/time/time.h"
 #include "media/cast/cast_config.h"
 #include "media/cast/cast_environment.h"
 #include "media/cast/transport/cast_transport_sender.h"
 #include "media/filters/gpu_video_accelerator_factories.h"
 
 namespace media {
 class AudioBus;
+class GpuVideoAcceleratorFactories;
 class VideoFrame;
-}
 
-namespace media {
 namespace cast {
+class AudioSender;
+class VideoSender;
 
-// This Class is thread safe.
-class FrameInput : public base::RefCountedThreadSafe<FrameInput> {
+class VideoFrameInput : public base::RefCountedThreadSafe<VideoFrameInput> {
  public:
-  // The video_frame must be valid until the callback is called.
-  // The callback is called from the main cast thread as soon as
-  // the encoder is done with the frame; it does not mean that the encoded frame
-  // has been sent out.
+  // Insert video frames into Cast sender. Frames will be encoded, packetized
+  // and sent to the network.
   virtual void InsertRawVideoFrame(
       const scoped_refptr<media::VideoFrame>& video_frame,
       const base::TimeTicks& capture_time) = 0;
 
+ protected:
+  virtual ~VideoFrameInput() {}
+
+ private:
+  friend class base::RefCountedThreadSafe<VideoFrameInput>;
+};
+
+class AudioFrameInput : public base::RefCountedThreadSafe<AudioFrameInput> {
+ public:
+  // Insert audio frames into Cast sender. Frames will be encoded, packetized
+  // and sent to the network.
   // The |audio_bus| must be valid until the |done_callback| is called.
   // The callback is called from the main cast thread as soon as the encoder is
   // done with |audio_bus|; it does not mean that the encoded data has been
   // sent out.
   virtual void InsertAudio(const AudioBus* audio_bus,
                            const base::TimeTicks& recorded_time,
                            const base::Closure& done_callback) = 0;
 
  protected:
-  virtual ~FrameInput() {}
+  virtual ~AudioFrameInput() {}
 
  private:
-  friend class base::RefCountedThreadSafe<FrameInput>;
+  friend class base::RefCountedThreadSafe<AudioFrameInput>;
 };
 
 // This Class is thread safe.

[Alpha Left Google, 2014/02/18 22:28:13]

This is actually not true. You might as well say all methods of CastSender must
be accessed on the main thread.

[mikhal1, 2014/03/05 21:44:05]

Done.

 // The provided CastTransportSender object will always be called from the main
 // cast thread.
-//  At least one of AudioSenderConfig and VideoSenderConfig have to be provided.
 class CastSender {
  public:
-  static CastSender* CreateCastSender(
+  static scoped_ptr<CastSender> Create(
       scoped_refptr<CastEnvironment> cast_environment,
-      const AudioSenderConfig* audio_config,
-      const VideoSenderConfig* video_config,
-      const scoped_refptr<GpuVideoAcceleratorFactories>& gpu_factories,
-      const CastInitializationCallback& cast_initialization,
+      const CastInitializationCallback& cast_initialization_cb,
       transport::CastTransportSender* const transport_sender);
 
   virtual ~CastSender() {}
 
-  // All audio and video frames for the session should be inserted to this
-  // object.
+  // All video frames for the session should be inserted to this object.
   // Can be called from any thread.

[Alpha Left Google, 2014/02/18 22:28:13]

This can only be called on the main thread because in CastSenderImpl
video_frame_input() returns a valid pointer only after InitializeVideo() is
called.

[mikhal1, 2014/03/05 21:44:05]

Done.

[mikhal1, 2014/03/05 21:44:05]

Done.

-  virtual scoped_refptr<FrameInput> frame_input() = 0;
+  virtual scoped_refptr<VideoFrameInput> video_frame_input() = 0;
+
+  // All audio frames for the session should be inserted to this object.
+  // Can be called from any thread.

[Alpha Left Google, 2014/02/18 22:28:13]

This can only be called on the main thread.

[mikhal1, 2014/03/05 21:44:05]

Done.

[mikhal1, 2014/03/05 21:44:05]

Done.

+  virtual scoped_refptr<AudioFrameInput> audio_frame_input() = 0;
 
   // All RTCP packets for the session should be inserted to this object.
-  // Can be called from any thread.
+  // This function and the callback must be called on the main thread.
   virtual transport::PacketReceiverCallback packet_receiver() = 0;
+
+  // Initialize the audio stack. Must be called in order to send audio frames.
+  virtual void InitializeAudio(const AudioSenderConfig& audio_config) = 0;

[Alpha Left Google, 2014/02/18 22:28:13]

These two methods should be called on the main thread as well.

[mikhal1, 2014/03/05 21:44:05]

Done.

+
+  // Initialize the video stack. Must be called in order to send video frames.
+  virtual void InitializeVideo(
+      const VideoSenderConfig& video_config,
+      const scoped_refptr<GpuVideoAcceleratorFactories>& gpu_factories) = 0;
 };
 
 }  // namespace cast
 }  // namespace media
 
 #endif  // MEDIA_CAST_CAST_SENDER_H_