YUV conversion on the GPU.

ui/surface/accelerated_surface_transformer_win.h

Index: ui/surface/accelerated_surface_transformer_win.h
diff --git a/ui/surface/accelerated_surface_transformer_win.h b/ui/surface/accelerated_surface_transformer_win.h
index e01804a43cf5ac0cd7fb1a4dc9337dc4fdc24522..b1984bbdd75e9bd335aef1e77c84fa34580200c4 100644
--- a/ui/surface/accelerated_surface_transformer_win.h
+++ b/ui/surface/accelerated_surface_transformer_win.h
@@ -56,26 +56,111 @@ class SURFACE_EXPORT AcceleratedSurfaceTransformer {
     const gfx::Rect& src_subrect,
     IDirect3DSurface9* dst_surface);
 
+  // Color format conversion from RGB to planar YV12 (also known as YUV420).
+  //
+  // YV12 is effectively a twelve bit per pixel format consisting of a full-
+  // size y (luminance) plane and half-width, half-height u and v (blue and
+  // red chrominance) planes. This method will allocate three lockable surfaces,
+  // one for each plane, and return them via the arguments |dst_y|, |dst_u|,
+  // and |dst_v|. These surface will be created with an ARGB D3DFORMAT, but
+  // should be interpreted as the appropriate single-byte format when locking.
+  //
+  // The dimensions of the outputs (when interpreted as single-component data)
+  // are as follows:
+  //   |dst_y| : width and height exactly |dst_size|
+  //   |dst_u| : width and height are each half of |dst_size|, rounded up.
+  //   |dst_v| : width and height are each half of |dst_size|, rounded up.
+  //
+  // If |src_texture|'s dimensions do not match |dst_size|, the source will be
+  // bilinearly interpolated during conversion.
+  //
+  // Returns true if successful. Caller must be certain to free the buffers
+  // even if this function returns false.
+  bool TransformRGBToYV12(
+      IDirect3DTexture9* src_texture,
+      const gfx::Size& dst_size,
+      IDirect3DSurface9** dst_y,
+      IDirect3DSurface9** dst_u,
+      IDirect3DSurface9** dst_v);
+
  private:
+  friend class AcceleratedSurfaceTransformerTest;
+
   enum ShaderCombo {
-    SIMPLE_TEXTURE,
+    ONE_TEXTURE_FLIP_Y,
+    RGB_TO_YV12_FAST__PASS_1_OF_2,
+    RGB_TO_YV12_FAST__PASS_2_OF_2,
+    RGB_TO_YV12_SLOW__PASS_1_OF_3,
+    RGB_TO_YV12_SLOW__PASS_2_OF_3,
+    RGB_TO_YV12_SLOW__PASS_3_OF_3,
     NUM_SHADERS
   };
 
+  // Efficient RGB->YV12 in two passes, but requires a device capable of writing
+  // multiple render targets at the same time.
+  //
+  // Returns true if successful.
+  bool TransformRGBToYV12_MRT(
+      IDirect3DTexture9* src_surface,
+      const gfx::Size& dst_size,
+      const gfx::Size& packed_y_size,
+      const gfx::Size& packed_uv_size,
+      IDirect3DSurface9* dst_y,
+      IDirect3DSurface9* dst_u,
+      IDirect3DSurface9* dst_v);
+
+  // Slower, less efficient RGB->YV12; does not require the device to have
+  // multiple render target capability. Runs at about half speed of the fast
+  // path.
+  //
+  // Returns true if successful.
+  bool TransformRGBToYV12_WithoutMRT(
+      IDirect3DTexture9* src_surface,
+      const gfx::Size& dst_size,
+      const gfx::Size& packed_y_size,
+      const gfx::Size& packed_uv_size,
+      IDirect3DSurface9* dst_y,
+      IDirect3DSurface9* dst_u,
+      IDirect3DSurface9* dst_v);
+
+  // Helper to allocate appropriately size YUV buffers, accounting for various
+  // roundings. The sizes of the buffers (in terms of ARGB pixels) are returned
+  // as |packed_y_size| and |packed_uv_size|.
+  //
+  // Returns true if successful. Caller must be certain to free the buffers
+  // even if this function returns false.
+  bool AllocYUVBuffers(
+      const gfx::Size& dst_size,
+      gfx::Size* packed_y_size,
+      gfx::Size* packed_uv_size,
+      IDirect3DSurface9** dst_y,
+      IDirect3DSurface9** dst_u,
+      IDirect3DSurface9** dst_v);
+
   // Set the active vertex and pixel shader combination.
+  //
+  // Returns true if successful.
   bool SetShaderCombo(ShaderCombo combo);
 
   // Intitializes a vertex and pixel shader combination from compiled bytecode.
-  bool InitShaderCombo(const BYTE vertex_shader_instructions[],
-                       const BYTE pixel_shader_instructions[],
-                       ShaderCombo shader_combo_name);
+  //
+  // Returns true if successful.
+  bool InitShaderCombo(ShaderCombo shader_combo_name,
+                       const BYTE vertex_shader_instructions[],
+                       const BYTE pixel_shader_instructions[]);
+
+  bool DoInit(IDirect3DDevice9* device);
+
+  void DrawScreenAlignedQuad(const gfx::Size& dst_size);
 
+  bool device_supports_multiple_render_targets();

[miu, 2012/12/27 21:40:17]

nit: const method, since this is just a simple getter?

[ncarter (slow), 2013/01/07 22:49:10]

Done.

   IDirect3DDevice9* device();
 
   base::win::ScopedComPtr<IDirect3DDevice9> device_;
   base::win::ScopedComPtr<IDirect3DVertexShader9> vertex_shaders_[NUM_SHADERS];
   base::win::ScopedComPtr<IDirect3DPixelShader9> pixel_shaders_[NUM_SHADERS];
+  bool device_supports_multiple_render_targets_;
   DISALLOW_COPY_AND_ASSIGN(AcceleratedSurfaceTransformer);
 };
 
-#endif  // UI_SURFACE_ACCELERATED_SURFACE_TRANSFORMER_WIN_H_
+#endif  // UI_SURFACE_ACCELERATED_SURFACE_TRANSFORMER_WIN_H_