Improving the decoder pipeline.

remoting/base/decoder_vp8.h

Index: remoting/base/decoder_vp8.h
diff --git a/remoting/base/decoder_vp8.h b/remoting/base/decoder_vp8.h
index 76fd5472b798497c7093d69ec41cc16a7b23108b..d0406990c17938ad3e83c1102b98670705c8f26c 100644
--- a/remoting/base/decoder_vp8.h
+++ b/remoting/base/decoder_vp8.h
@@ -18,15 +18,17 @@ class DecoderVp8 : public Decoder {
   virtual ~DecoderVp8();
 
   // Decoder implementations.
-  virtual void Initialize(scoped_refptr<media::VideoFrame> frame) OVERRIDE;
+  virtual void Initialize(const SkISize& screen_size) OVERRIDE;
   virtual DecodeResult DecodePacket(const VideoPacket* packet) OVERRIDE;
-  virtual void GetUpdatedRegion(SkRegion* region) OVERRIDE;
   virtual bool IsReadyForData() OVERRIDE;
   virtual void Reset() OVERRIDE;
   virtual VideoPacketFormat::Encoding Encoding() OVERRIDE;
-  virtual void SetOutputSize(const SkISize& size) OVERRIDE;
-  virtual void SetClipRect(const SkIRect& clip_rect) OVERRIDE;
-  virtual void RefreshRegion(const SkRegion& region) OVERRIDE;
+  virtual void UpdateRegion(const SkRegion& region) OVERRIDE;
+  virtual void Draw(const SkISize& view_size,
+                    const SkIRect& clip_area,
+                    uint8* image_buffer,
+                    int image_stride,
+                    SkRegion* output_region) OVERRIDE;
 
  private:
   enum State {
@@ -35,38 +37,19 @@ class DecoderVp8 : public Decoder {
     kError,
   };
 
-  // Return true if scaling is enabled
-  bool DoScaling() const;
-
-  // Perform color space conversion on the specified region.
-  // Writes the updated region to |output_region|.
-  void ConvertRegion(const SkRegion& region,
-                     SkRegion* output_region);
-
-  // Perform scaling and color space conversion on the specified
-  // region.  Writes the updated rectangles to |output_region|.
-  void ScaleAndConvertRegion(const SkRegion& region,
-                             SkRegion* output_region);
-
   // The internal state of the decoder.
   State state_;
 
-  // The video frame to write to.
-  scoped_refptr<media::VideoFrame> frame_;
-
   vpx_codec_ctx_t* codec_;
 
   // Pointer to the last decoded image.
   vpx_image_t* last_image_;
 
-  // The region updated by the most recent decode.
+  // The region updated that hasn't been copied to the screen yet.
   SkRegion updated_region_;

[Wez, 2012/02/07 01:56:31]

I think this needs renaming, and the semantics clarifying.  This region gets
populated either from an incoming update, or an UpdateRegion call, and cleared
after each Draw().

But what if we Draw only a portion of the desktop, but are keeping a full-sized
framebuffer, i.e. we're just using clipping to optimize out some work?  Then
we've actually lost information on what changed in those other regions.

[alexeypa (please no reviews), 2012/02/15 23:06:22]

Now we validate only the painted area.

 
-  // Clipping rect for the output of the decoder.
-  SkIRect clip_rect_;
-
   // Output dimensions.
-  SkISize output_size_;
+  SkISize screen_size_;
 
   DISALLOW_COPY_AND_ASSIGN(DecoderVp8);
 };