Add correct support for videos with YUVJ420P color format, in the software conversion path.

media/base/yuv_convert.h

Index: media/base/yuv_convert.h
diff --git a/media/base/yuv_convert.h b/media/base/yuv_convert.h
index 8f64c79689a3dfaf33a1944d23d4e1ac66655f6b..2fe5acaefac299cfac46066b68365ad19bb65318 100644
--- a/media/base/yuv_convert.h
+++ b/media/base/yuv_convert.h
@@ -22,12 +22,18 @@
 namespace media {
 
 // Type of YUV surface.
-// The value of these enums matter as they are used to shift vertical indices.
 enum YUVType {
-  YV16 = 0,  // YV16 is half width and full height chroma channels.
-  YV12 = 1,  // YV12 is half width and half height chroma channels.
+  YV16  = 0,  // YV16 is half width and full height chroma channels.
+  YV12  = 1,  // YV12 is half width and half height chroma channels.
+  YV12J = 2,  // YV12J is the same as YV12, but in JPEG color range.
 };
 
+// Get the appropriate value to bitshift by for vertical indices.
+int GetVerticalShift(YUVType type);
+
+#define GET_LOOKUP_TABLE(type) \

[rileya (GONE FROM CHROMIUM), 2014/04/22 17:57:50]

Ugly macro, since we can't return a sized/multidimensional array from a function
in C++. Making all the conversion functions take a plain pointer would let us
use a function instead, but I sort of like making the table size explicit in the
function signatures ("table[foo][bar]" also looks nicer than "table[foo + bar *
1024]"). Thoughts?

[scherkus (not reviewing), 2014/04/22 18:53:33]

so there is some heinous syntax you can use to pass back a const-reference to a
sized array

const int (&GetLookupTable(YUVType type))[1024][4] {
  ...
}

since the arrays are global statics it's safe to pass back const-ref

downside is all the parameters to functions get a bit ugly too:

void MyFunc(const int (&table)[1024][4]) {
  ...
}

[rileya (GONE FROM CHROMIUM), 2014/04/23 21:23:51]

Looks like that worked without needing to modify the parameters (though I won't
be too surprised if visual studio chokes on it...).

+  ((type) == YV12J ? kCoefficientsRgbY_JPEG : kCoefficientsRgbY)
+
 // Mirror means flip the image horizontally, as in looking in a mirror.
 // Rotate happens after mirroring.
 enum Rotate {