ChangeFSI and artefacts when scaling down

I recently scaled down some images that had custom 256 colour palettes (they had been created from DrawFiles using InterGIF).

Depending on the scaling factor, there would be grey artefacts on the bottom most or rightmost line of the image. How dark the grey depending upon how many lines were missing due to the scaling.

It seems to me that ChangeFSI, if in doubt, invents the extra pixels but colours them black. Which leads to problems if it’s a white background image.

The “fix” is to pad the image with extra lines until it resizes cleanly. But it might be better to have a way of telling ChangeFSI what to consider the background to be (even if only “black or white”) or to have it repeat the final line of the image, or something.

ChangeFSI is, still, a pretty useful tool. I have several image resizer apps on my phone, and they aren’t bad when doing a straight 1:2 or 1:4 resize, but give it an odd size like 2:3 or ask it to scale to a certain width and the results are appalling. Worse, in some cases, than getting SpriteExtend to do the same job. It’s as if nobody has ever heard of dithering. :/

So good old ChangeFSI, even if it takes an eternity to load JPEGs, is still a reliable way to scale to arbitrary weird sizes and arrive at something useful.

Which version of ChangeFSI are you using? The symptoms you describe sound suspiciously like this bug which was fixed in ChangeFSI 1.59 (November 2016).

Interesting. I thought I’d copied it from the latest Harddisc4 archive (to get PNG export). I’ll need to check the versions next time I have the machine on.

But if it’s been fixed, then that’s great! ;)