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 pngout
If Hit
Enter
and press 'y'
when asked if you wish to install the package, along with any
dependencies. After it is
installed, source your ~/.bashrc
file: ~>
source ~/.bashrc
If
you
need help with the
syntax, type: ~>
pngout --help
I've found the program works
well, and have used it to compress a number of images that are used on
this website.