pngout is a program that optimizes the size of a PNG file using a lossless algorithm to make their sizes more friendly for use on the web.
I have created an RPM that can be installed using via the kriehn repository using yum:
~> sudo yum install pngoutIf Hit Enter and press 'y' when asked if you wish to install the package, along with any dependencies. If you need help with the syntax, type:
~> pngout --helpI've found the program works well, and have used it to compress a number of images that are used on this website.