pngcrush

PNG image compression utility.

Compress a PNG file:

pngcrush {{in.png}} {{out.png}}

Compress all PNGs and output to directory:

pngcrush -d {{path/to/output}} *.png

Compress PNG file with all 114 available algorithms and pick the best result:

pngcrush -rem allb -brute -reduce {{in.png}} {{out.png}}