Scaling revisited

Krita’s scaling 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 genericĀ  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.