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. To install it, go to the pngout Linux/Mac OS X port page for the program:
Click on the Dynamic download link under Linux, since FC6 uses a glibc version that is greater than 2.3.5. This will download the current version, which at the time of this writing, is pngout-20070430-linux.tar.gz. Once downloaded, create an appropriate directory to install pngout under /usr/local/src/pngout:
~>
sudo mkdir -p /usr/local/src/pngout/pngout-20070430
Copy the tarball to the directory: ~>
sudo cp ~/Download/pngout-20070430-linux.tar.gz
/usr/local/src/pngout/pngout-20070430/.
Change into the pngout/pngout-20070110
directory: ~>
cd /usr/local/src/pngout/pngout-20070430
and decompress the tarball: ~>
sudo tar vfzx pngout-20070430-linux.tar.gz
Once the package has been
decompressed, delete the tarball: ~>
sudo rm pngout-20070430-linux.tar.gz
You should notice that pngout
has already been
compiled, and what was decompressed by the tarball is several binary
files. The file we are interested in is pngout-linux-i686.
To use it, create a soft link from /usr/local/bin
to its location: ~>
sudo ln -s /usr/local/src/pngout/pngout-20070430/pngout-linux-i686
/usr/local/bin/pngout
Finally, source the ~/.tcshrc
file: ~>
source ~/.tcshrc
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.