Support for YUV 4:4:4 subsampling in vpx decoder.

media/filters/vpx_video_decoder.cc

Index: media/filters/vpx_video_decoder.cc
diff --git a/media/filters/vpx_video_decoder.cc b/media/filters/vpx_video_decoder.cc
index 894f8712c70fbf8c27efdd20f3c82d898ab86910..5cc005204855297a135345fe2fa1b61b7a1a028e 100644
--- a/media/filters/vpx_video_decoder.cc
+++ b/media/filters/vpx_video_decoder.cc
@@ -450,27 +450,40 @@ void VpxVideoDecoder::CopyVpxImageTo(const vpx_image* vpx_image,
                                      scoped_refptr<VideoFrame>* video_frame) {
   CHECK(vpx_image);
   CHECK(vpx_image->fmt == VPX_IMG_FMT_I420 ||
-        vpx_image->fmt == VPX_IMG_FMT_YV12);
+        vpx_image->fmt == VPX_IMG_FMT_YV12 ||
+        vpx_image->fmt == VPX_IMG_FMT_I444);
+
+  VideoFrame::Format codec_format;

[scherkus (not reviewing), 2014/05/29 02:30:26]

nit: we typically try to initialize variables to some known value as the
compiler will do the right thing when optimizing the code

(if your conditions below ever get shuffled around, it's better to have known
values there in the first place so we don't end up with uninitialized values
down the road)

[sandersd (OOO until July 31), 2014/05/29 20:39:09]

Done. I don't think that it's easier to read, but you are right that it's a
little safer.

+  int uv_rows;
+
+  if (vpx_image->fmt == VPX_IMG_FMT_I444) {
+    CHECK(!vpx_codec_alpha_);
+    codec_format = VideoFrame::YV24;
+    uv_rows = vpx_image->d_h;
+  } else {
+    codec_format = vpx_codec_alpha_ ? VideoFrame::YV12A : VideoFrame::YV12;
+    uv_rows = (vpx_image->d_h + 1) / 2;
+  }
 
   gfx::Size size(vpx_image->d_w, vpx_image->d_h);
 
   if (!vpx_codec_alpha_ && memory_pool_) {
     *video_frame = VideoFrame::WrapExternalYuvData(
-                       VideoFrame::YV12,
-                       size, gfx::Rect(size), config_.natural_size(),
-                       vpx_image->stride[VPX_PLANE_Y],
-                       vpx_image->stride[VPX_PLANE_U],
-                       vpx_image->stride[VPX_PLANE_V],
-                       vpx_image->planes[VPX_PLANE_Y],
-                       vpx_image->planes[VPX_PLANE_U],
-                       vpx_image->planes[VPX_PLANE_V],
-                       kNoTimestamp(),
-                       memory_pool_->CreateFrameCallback(vpx_image->fb_priv));
+        codec_format,
+        size, gfx::Rect(size), config_.natural_size(),
+        vpx_image->stride[VPX_PLANE_Y],
+        vpx_image->stride[VPX_PLANE_U],
+        vpx_image->stride[VPX_PLANE_V],
+        vpx_image->planes[VPX_PLANE_Y],
+        vpx_image->planes[VPX_PLANE_U],
+        vpx_image->planes[VPX_PLANE_V],
+        kNoTimestamp(),
+        memory_pool_->CreateFrameCallback(vpx_image->fb_priv));
     return;
   }
 
   *video_frame = frame_pool_.CreateFrame(
-      vpx_codec_alpha_ ? VideoFrame::YV12A : VideoFrame::YV12,
+      codec_format,
       size,
       gfx::Rect(size),
       config_.natural_size(),
@@ -482,11 +495,11 @@ void VpxVideoDecoder::CopyVpxImageTo(const vpx_image* vpx_image,
              video_frame->get());
   CopyUPlane(vpx_image->planes[VPX_PLANE_U],
              vpx_image->stride[VPX_PLANE_U],
-             (vpx_image->d_h + 1) / 2,
+             uv_rows,
              video_frame->get());
   CopyVPlane(vpx_image->planes[VPX_PLANE_V],
              vpx_image->stride[VPX_PLANE_V],
-             (vpx_image->d_h + 1) / 2,
+             uv_rows,
              video_frame->get());
   if (!vpx_codec_alpha_)
     return;