Provide a Chrome-owned buffer to FFmpeg for video decoding, instead of

media/base/video_frame.h

Index: media/base/video_frame.h
===================================================================
--- media/base/video_frame.h	(revision 140753)
+++ media/base/video_frame.h	(working copy)
@@ -38,20 +38,45 @@
   };
 
   // Creates a new frame in system memory with given parameters. Buffers for
-  // the frame are allocated but not initialized.
+  // the frame are allocated but not initialized. If bytes_per_row and
+  // bytes_per_row_uv are zero, they are initialized to a default value
+  // suitable for the given format.
   static scoped_refptr<VideoFrame> CreateFrame(
       Format format,
       size_t width,
       size_t height,
+      size_t bytes_per_row,
+      size_t bytes_per_uv_row,

[Ami GONE FROM CHROMIUM, 2012/06/08 19:11:04]

These two args don't make sense to me, because they overlap semantically with
the information content of width+format.  

Can this be reduced to an alignment/padding requirement instead?  I think that
would make for a much saner API.

+      size_t aligned_height,
       base::TimeDelta timestamp,
       base::TimeDelta duration);
+  static scoped_refptr<VideoFrame> CreateFrame(
+      Format format,
+      size_t width,
+      size_t height,
+      base::TimeDelta timestamp,
+      base::TimeDelta duration) {
+    return CreateFrame(format, width, height, 0, 0, 0,
+                       timestamp, duration);
+  }
 
   // Call prior to CreateFrame to ensure validity of frame configuration. Called
-  // automatically by VideoDecoderConfig::IsValidConfig().
+  // automatically by VideoDecoderConfig::IsValidConfig(). If bytes_per_row and
+  // bytes_per_uv_row are non-zero, they are also checked to be valid strides
+  // for the given buffer size and format.
   static bool IsValidConfig(
       Format format,
       size_t width,
-      size_t height);
+      size_t height,
+      size_t bytes_per_row,
+      size_t bytes_per_uv_row,
+      size_t aligned_height);
+  static bool IsValidConfig(
+      Format format,
+      size_t width,
+      size_t height) {
+    return IsValidConfig(format, width, height, 0, 0, 0);
+  }
 
   // Wraps a native texture of the given parameters with a VideoFrame.  When the
   // frame is destroyed |no_longer_needed.Run()| will be called.
@@ -130,8 +155,9 @@
   virtual ~VideoFrame();
 
   // Used internally by CreateFrame().
-  void AllocateRGB(size_t bytes_per_pixel);
-  void AllocateYUV();
+  void AllocateRGB(size_t bytes_per_row, size_t aligned_height);
+  void AllocateYUV(size_t bytes_per_y_row, size_t bytes_per_uv_row,
+                   size_t aligned_height);
 
   // Used to DCHECK() plane parameters.
   bool IsValidPlane(size_t plane) const;