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

media/base/video_util.h

Index: media/base/video_util.h
diff --git a/media/base/video_util.h b/media/base/video_util.h
index 2dec7e9371013ff3bf0442cb798cef0c90104659..dbef16e3e046348c2bec9a20f7bd15552cfece0f 100644
--- a/media/base/video_util.h
+++ b/media/base/video_util.h
@@ -97,6 +97,14 @@ MEDIA_EXPORT void CopyRGBToVideoFrame(const uint8_t* source,
 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_