media: Optimize HW Video to 2D Canvas copy.

media/filters/skcanvas_video_renderer.h

 // Copyright (c) 2012 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_FILTERS_SKCANVAS_VIDEO_RENDERER_H_
 #define MEDIA_FILTERS_SKCANVAS_VIDEO_RENDERER_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "media/base/media_export.h"
 #include "media/base/video_rotation.h"
+#include "media/filters/context_3d_provider.h"
 #include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/gfx/rect.h"
 
-class SkCanvas;
-
 namespace media {
 
 class VideoFrame;
 class VideoImageGenerator;
 
 // Handles rendering of VideoFrames to SkCanvases, doing any necessary YUV
 // conversion and caching of resulting RGB bitmaps.
 class MEDIA_EXPORT SkCanvasVideoRenderer {
  public:
   SkCanvasVideoRenderer();
   ~SkCanvasVideoRenderer();
 
   // Paints |video_frame| on |canvas|, scaling and rotating the result to fit
   // dimensions specified by |dest_rect|.
   //
   // Black will be painted on |canvas| if |video_frame| is null.
   void Paint(const scoped_refptr<VideoFrame>& video_frame,
              SkCanvas* canvas,
              const gfx::RectF& dest_rect,
              uint8 alpha,
              SkXfermode::Mode mode,
-             VideoRotation video_rotation);
+             VideoRotation video_rotation,
+             const Context3DProvider& context_provider);
 
   // Copy |video_frame| on |canvas|.
   void Copy(const scoped_refptr<VideoFrame>&, SkCanvas* canvas);
 
+  static void CopyVideoFrameTextureToGLTexture(gpu::gles2::GLES2Interface* gl,

[scherkus (not reviewing), 2014/10/30 20:40:13]

can we get documentation?

for example, it'd be good to highlight that this requires NATIVE_TEXTURE

[dshwang, 2014/10/31 09:29:17]

Done.

+                                               media::VideoFrame* video_frame,

[scherkus (not reviewing), 2014/10/30 20:40:13]

nit: typically we pass these as const-ref (you can also drop the media:: prefix)

const scoped_refptr<VideoFrame>& video_frame

[danakj, 2014/10/30 21:04:20]

If you don't need a reference, passing a T* is more clear that you are not
passing something that you can take a reference on. I would recommend this over
const scoped_refptr<T>& when you don't need to take a ref on T.

[dshwang, 2014/10/31 09:29:17]

I preserve T* because it doesn't need to take a ref.
Paint() also has used T* before introducing VideoImageGenerator, which takes a
ref.

+                                               unsigned int texture,
+                                               unsigned int level,
+                                               unsigned int internal_format,
+                                               unsigned int type,
+                                               bool premultiply_alpha,
+                                               bool flip_y);
+
  private:
   void ResetLastFrame();
   void ResetAcceleratedLastFrame();
 
   // An RGB bitmap and corresponding timestamp of the previously converted
   // video frame data by software color space conversion.
   SkBitmap last_frame_;
   base::TimeDelta last_frame_timestamp_;
   // If |last_frame_| is not used for a while, it's deleted to save memory.
   base::DelayTimer<SkCanvasVideoRenderer> frame_deleting_timer_;
 
   // This is a hardware accelerated copy of the frame generated by
   // |accelerated_generator_|.
   // It's used when |canvas| parameter in Paint() is Ganesh canvas.
   // Note: all GrContext in SkCanvas instances are same.
   SkBitmap accelerated_last_frame_;
   VideoImageGenerator* accelerated_generator_;
   base::TimeDelta accelerated_last_frame_timestamp_;
   base::DelayTimer<SkCanvasVideoRenderer> accelerated_frame_deleting_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(SkCanvasVideoRenderer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_SKCANVAS_VIDEO_RENDERER_H_