[cairo] [PATCH] Revert "image: Use convolution filters for sample reconstruction when downscaling"

Bill Spitzak spitzak at gmail.com
Fri May 16 18:19:39 PDT 2014


Just trying the "scale" sample program in pixman, it is pretty obvious 
what works:

If scale < 1 (ie downscaling) then the "reconstruction" filter must be 
Impulse, and the "sampling" filter must be Linear or higher (Box appears 
to be broken). You can set the subsample value to 0.

If scale > 1 (ie upscaling) then the "sampling" filter must be Impulse 
and the "reconstruction" filter must be Linear or higher (again Box 
appears to be broken). And subsample must be non-zero, it looks like 
floor(scale) works.


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