Refactor VideoDenoiser to work with I420Buffer, not VideoFrame.

webrtc/common_video/video_frame_buffer.cc

Index: webrtc/common_video/video_frame_buffer.cc
diff --git a/webrtc/common_video/video_frame_buffer.cc b/webrtc/common_video/video_frame_buffer.cc
index 700dcaf02b7af098798eb51e344f065b232a8700..91c288778e7149199db3989d79557fbc9bd0c211 100644
--- a/webrtc/common_video/video_frame_buffer.cc
+++ b/webrtc/common_video/video_frame_buffer.cc
@@ -207,6 +207,26 @@ rtc::scoped_refptr<I420Buffer> I420Buffer::Copy(
   return copy;
 }
 
+rtc::scoped_refptr<I420Buffer> I420Buffer::CopyKeepStride(
+    const rtc::scoped_refptr<VideoFrameBuffer>& buffer) {
+  int width = buffer->width();
+  int height = buffer->height();
+  int stride_y = buffer->StrideY();
+  int stride_u = buffer->StrideU();
+  int stride_v = buffer->StrideV();
+  rtc::scoped_refptr<I420Buffer> copy = new rtc::RefCountedObject<I420Buffer>(
+      width, height, stride_y, stride_u, stride_v);
+  RTC_CHECK(libyuv::I420Copy(buffer->DataY(), stride_y,
+                             buffer->DataU(), stride_u,
+                             buffer->DataV(), stride_v,
+                             copy->MutableDataY(), stride_y,
+                             copy->MutableDataU(), stride_u,
+                             copy->MutableDataV(), stride_v,
+                             width, height) == 0);
+
+  return copy;

[jackychen, 2016/06/09 19:08:36]

Could you use a better name instead of copy? At least, we should know it is a
buffer copy.

[nisse-webrtc, 2016/06/10 11:09:19]

To me, "copy" seems quite clear from the context, but I can try to improve the
naming. Would it be clearer if I rename buffer --> src (the input argument) and
copy --> buffer (the returned value)?

+}
+
 NativeHandleBuffer::NativeHandleBuffer(void* native_handle,
                                        int width,
                                        int height)