[cairo] image downsampling quality

Behdad Esfahbod behdad at behdad.org
Thu Jan 2 03:23:52 PST 2014

On 14-01-02 07:09 PM, Ray Gardener wrote:
> When using e.g. cairo_pattern_set_filter(pattern, CAIRO_FILTER_BEST) and
> the pattern uses a bitmap surface, is the filter only for upsampling?
> I have high-res bitmaps that, when drawn to occupy fewer canvas pixels
> (downsampled),
> they look like they're being nearest neighbour filtered.

I think it's bilinear, which means if you are reducing to less than 50%, it
misses pixels.

There's been tons of talk and patches to fix this in pixman over the years.
I'm not sure what the current status is.


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