Memory copy the VideoFrame to match the requirement for HW encoders.

media/base/video_util.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_BASE_VIDEO_UTIL_H_
 #define MEDIA_BASE_VIDEO_UTIL_H_
 
 #include <stdint.h>
 
 #include "base/memory/ref_counted.h"
@@ skipping 79 matching lines @@
 // Fills the regions outside |region_in_frame| with black.
 MEDIA_EXPORT void CopyRGBToVideoFrame(const uint8_t* source,
                                       int stride,
                                       const gfx::Rect& region_in_frame,
                                       VideoFrame* frame);
 
 // Converts a frame with YV12A format into I420 by dropping alpha channel.
 MEDIA_EXPORT scoped_refptr<VideoFrame> WrapAsI420VideoFrame(
     const scoped_refptr<VideoFrame>& frame);
 
+// Copy I420 video frame to match the required coded size and pad the region
+// outside visible rect repeatly with the last column / row. The required coded

[xhwang, 2016/05/04 21:08:29]

Could you please summarize why we want to convert a VideoFrame to one with
larger coded size, and why we want to do the padding?

[xjz, 2016/05/05 01:15:56]

Done.

+// size should be larger than or equal to the visible size, since the visible
+// region in both frames should be identical. Return false if copy is not
+// successful.

[xhwang, 2016/05/04 21:08:29]

Also mention that this function could be expensive (performance-wise).

[xjz, 2016/05/05 01:15:56]

Done.

+MEDIA_EXPORT bool I420CopyWithPadding(const VideoFrame& src_frame,
+                                      VideoFrame* dst_frame) WARN_UNUSED_RESULT;

[xhwang, 2016/05/04 21:08:29]

Could you please add some unittests?

[xjz, 2016/05/05 01:15:56]

Done.

+
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_UTIL_H_