The Python Imaging Library (PIL) adds image processing capabilities to your Python interpreter. This library supports many file formats, and provides powerful image processing and graphics capabilities.
The current stable version is 1.1.7, released in November 2009. The next release will be 1.2, with “early 2011” as the release target.
Prebuilt versions of PIL are available in most Linux package repositories. Try sudo aptitude install python-imaging, or the corresponding command for your Linux version. You can also search for it