Execute with PHP this command line tools
pngcrush -rem gAMA -rem cHRM -rem iCCP -rem sRGB -brute -l 9 -max -reduce -m 0 -q IMAGE optipng -o7 -q pngout.png pngout pngout.png -q -y -k0 -s0 advpng -z -4 pngout.png > /dev/null
- pngcrush
- OptiPNG
- pngout
- advpng
