Krita's scaled used to be, at least in my memory, a lot better than it's
now. The change came when we went from scaling code that was channel-depth
dependent and scaling-specific to channel-depth independent generic transform
code. Today I put the old code back and special cased it for 8 bit rgb, cmyk
and grayscale code. Let's see if it makes any difference. The image
was scaled from 1200 pixels width to 400 using the default settings. Just
open the dialog, set the width and press enter. That's what I always
do anyways.
The generic code:
Michael Thaler's quality optimized code:
Gimp:
And now blown up to 800 percent:
The generic code:
Michael Thaler's quality optimized code:
Gimp:
The Gimp may still be a little better than Michael's code, which
gives results that are just a little fuzzier, but the quality difference
between the generic Krita code and Michael's code show that my memory
hadn't betrayed me.