[FFmpeg-devel] [PATCH] Set generic yuv420 sampling in yuv4mpeg by default

David Conrad lessen42
Fri May 8 06:12:58 CEST 2009

On May 7, 2009, at 11:43 PM, David Conrad wrote:

> Hi,
> As discovered in #x264, the dump_psnr tool in Thusnelda actually  
> cares about chroma sample positions. This should probably be more  
> correct; I don't know for sure which codecs define which positioning.

Also I should mention that this is the reason x264 scored so badly on  
the latest Thusnelda update. dump_psnr shifted x264's chroma a half  
pixel left and this resulted in 4 db PSNR lost.

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