ImageMagick with alpha thresholds did the trick.
magick mogrify -path ./ -resize 25% -quality 100 -channel alpha -threshold 50% +channel *.png
Hi!
I really like the aesthetics here and bought this pack along with couple of others. What tool would you suggest to downscale these and pack to a sheet? I tried one method, but it replaced few pixels here and there with a wrong color. This is problematic with continuous color, such as road.
Thanks in advance!