diff options
Diffstat (limited to 'chrome/renderer/media/video_renderer_impl.h')
-rw-r--r-- | chrome/renderer/media/video_renderer_impl.h | 150 |
1 files changed, 136 insertions, 14 deletions
diff --git a/chrome/renderer/media/video_renderer_impl.h b/chrome/renderer/media/video_renderer_impl.h index 38a7124..134cc9a 100644 --- a/chrome/renderer/media/video_renderer_impl.h +++ b/chrome/renderer/media/video_renderer_impl.h @@ -11,31 +11,37 @@ // Paint() // SetRect() -#ifndef CHROME_RENDERER_MEDIA_VIDEO_RENDERER_H_ -#define CHROME_RENDERER_MEDIA_VIDEO_RENDERER_H_ +#ifndef CHROME_RENDERER_MEDIA_VIDEO_RENDERER_IMPL_H_ +#define CHROME_RENDERER_MEDIA_VIDEO_RENDERER_IMPL_H_ +#include <deque> + +#include "base/lock.h" +#include "base/task.h" #include "base/gfx/platform_canvas.h" +#include "chrome/renderer/webmediaplayer_delegate_impl.h" #include "base/gfx/rect.h" #include "media/base/factory.h" #include "media/base/filters.h" +#include "webkit/glue/webmediaplayer_delegate.h" -class WebMediaPlayerDelegateImpl; +class SubmitReadsTask; class VideoRendererImpl : public media::VideoRenderer { public: - VideoRendererImpl(WebMediaPlayerDelegateImpl* delegate); - // media::MediaFilter implementation. virtual void Stop(); // media::VideoRenderer implementation. virtual bool Initialize(media::VideoDecoder* decoder); - // Called from WebMediaPlayerDelegateImpl from WebKit's main thread. - void Paint(skia::PlatformCanvas* canvas, const gfx::Rect& rect); + // Methods for painting called by the WebMediaPlayerDelegateImpl + // TODO(ralphl): What the *$*%##@ is this? What does it mean? How do we + // treat the "rect"? Is is clipping? + virtual void SetRect(const gfx::Rect& rect); - // Called from WebMediaPlayerDelegateImpl from WebKit's main thread. - void SetRect(const gfx::Rect& rect); + // TODO(ralphl): What is this rect? Is it relative to the canvas? + virtual void Paint(skia::PlatformCanvas* canvas, const gfx::Rect& rect); // Static method for creating factory for this object. static media::FilterFactory* CreateFactory( @@ -44,17 +50,133 @@ class VideoRendererImpl : public media::VideoRenderer { VideoRendererImpl, WebMediaPlayerDelegateImpl*>(delegate); } + // Implementation of AssignableBuffer<this>::OnAssignment method. + void OnAssignment(media::VideoFrame* video_frame); + + private: + friend class SubmitReadsTask; + friend class media::FilterFactoryImpl1<VideoRendererImpl, + WebMediaPlayerDelegateImpl*>; + + // Constructor and destructor are private. Only the filter factory is + // allowed to create instances. + explicit VideoRendererImpl(WebMediaPlayerDelegateImpl* delegate); + virtual ~VideoRendererImpl(); + // Answers question from the factory to see if we accept |format|. static bool IsMediaFormatSupported(const media::MediaFormat* format); - protected: - virtual ~VideoRendererImpl(); + // Used by the IsMediaFormatSupported and Initialize methods. Examines the + // |media_format| and returns true if the format is supported. Both output + // parameters, |width_out| and |height_out| are required and must not be NULL. + static bool ParseMediaFormat(const media::MediaFormat* media_format, + int* width_out, + int* height_out); - private: + // Used internally to post a task that will call the SubmitReads() method. + // The |lock_| must be acquired before calling this method. If the value of + // |number_of_reads_needed_| is 0 or if there is already a pending task then + // this method simply returns and does not post a new task. + void PostSubmitReadsTask(); + + // Examines the |number_of_reads_needed_| member and calls the decoder to + // read the necessary number of frames. + void SubmitReads(); + + // For simplicity, we use the |delegate_| member to indicate if we have been + // stopped or not. + bool IsRunning() const { return (delegate_ != NULL); } + + // Throw away all frames in the queue. The |lock_| must have been acquired + // before calling this method. + void DiscardAllFrames(); + + // This method is always called with the object's |lock_| acquired.. + // The bool return value indicates weather or not the front of the queue has + // been updated. If this method returns true, then the front of the queue + // is a new video frame, otherwise, the front is the same as the last call. + // Given the current |time|, this method updates the state of the video frame + // queue. The caller may pass in a |new_frame| which will be added to the + // queue in the appropriate position based on the frame's timestamp. The + // |front_frame_out| and |time_next_frame_out| parameters are both optional + // and can be NULL. If |front_frame_out| is non-NULL, then it is returned as + // either NULL, which indicates that there are no frames in the queue, or + // it will be a pointer to the frame at the front of the queue. NOTE: THIS + // FRAME'S REFERENCE COUNT HAS BEEN INCREMENTED BY THIS CALL. THE + // CALLING FUNCTION MUST CALL |front_frame_out|->Release(); + // If the |time_next_frame_out| parameter is non-NULL then it will be assigned + // the stream time of the next frame in the queue. This is used by the Paint + // method to schedule a time update callback at the appropriate presentation + // time for the next frame. + bool UpdateQueue(base::TimeDelta time, + media::VideoFrame* new_frame, + media::VideoFrame** front_frame_out, + base::TimeDelta* time_next_frame_out); + + // Internal method used by the Paint method to convert the specified video + // frame to RGB, placing the converted pixels in the |current_frame_| bitmap. + void CopyToCurrentFrame(media::VideoFrame* video_frame); + + // Called when the clock is updated by the audio renderer of when a scheduled + // callback is called based on the interpolated current position of the media + // stream. + void TimeUpdateCallback(base::TimeDelta time); + + // Critical section. There is only one for this object. Used to serialize + // access to the following members: + // |queue_| for obvious reasons + // |delegate_| because it is used by methods that can be called from random + // threads to determine if the render has been stopped (it will + // be NULL if stopped) + // |submit_reads_task_| to prevent multiple scheduling of the task and to + // allow for safe cancelation of the task. + // |current_frame_timestamp_| because member is used by the render + // thread in the Paint method and by DiscardAllFrames which can be + // called on the decoder's thread when a seek occurs. + // |number_of_reads_needed_| is modified by UpdateQueue from the decoder + // thread, the renderer thread, and the pipeline thread. + // |preroll_complete_| has a very small potential race condition if the + // OnAssignment method were reentered for the last frame in the queue + // and an end-of-stream frame. + Lock lock_; + + // Pointer to our parent object that is called to request repaints. WebMediaPlayerDelegateImpl* delegate_; + // Pointer to the decoder that will feed us with video frames. + scoped_refptr<media::VideoDecoder> decoder_; + + // If non-NULL then a task has been scheduled to submit read requests to the + // video decoder. + CancelableTask* submit_reads_task_; + + // The number of buffers we need to request. This member is updated by any + // method that removes frames from the queue, such as UpdateQueue and + // DiscardAllFrames. + int number_of_reads_needed_; + + // An RGB bitmap of the current frame. Note that we use the timestamp to + // determine if the frame contents need to be color space converted, or if the + // |current_frame_| member contains the correct image for the queue front. + SkBitmap current_frame_; + base::TimeDelta current_frame_timestamp_; + + // TODO(ralphl): Try to understand all of the various "rect" and dimension + // aspects of the renderer and document it so that other people can understand + // it too. I can not accurately describe what the role of this member is now. + gfx::Rect rect_; + + // The queue of video frames. The front of the queue is the frame that should + // be displayed. + typedef std::deque<media::VideoFrame*> VideoFrameQueue; + VideoFrameQueue queue_; + + // True if we have received a full queue of video frames from the decoder. + // We don't call FilterHost::InitializationComplete() until the the queue + // is full. + bool preroll_complete_; + DISALLOW_COPY_AND_ASSIGN(VideoRendererImpl); }; -#endif // CHROME_RENDERER_MEDIA_VIDEO_RENDERER_H_ - +#endif // CHROME_RENDERER_MEDIA_VIDEO_RENDERER_IMPL_H_ |