[FFmpeg-devel] [PATCH] Fix bit-exactness of MMX avg_no_rnd_pixels

[David Conrad]

Hi,

As I found in VC1, the MMX versions of avg_no_rnd_pixels are not  
identical with their C counterparts. The problem is that the C  
versions use (a+b+1)>>1 to average the interpolated pixels with the  
existing pixels, while the MMX versions use the same (a+b)>>1 used for  
interpolation.

This fixes the problem by adding an OP_AVG macro to always use (a+b 
+1)>>1 where needed.

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