I'm using imagemin-pngquant with gulp, and when I save big png file (above 500kB maybe) it writes gulp-imagemin: Minified 1 image (saved 0 B - 0%), and image size doesn't change. So I have to go to tinypng.com and compress it there :(
Looked at imagemin docs but can't find there anything about filesize limit.
Running on Windows 8.1