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Zak allows you to select one or more MP3 files and convert them into a single MP3 or MP4/M4A/M4B file. The primary use for Zak is audio books. Most audio books are distributed in several files, usually one per chapter. Converting these files into a single .m4b allows one to take advantage of the iPod's bookmarking features.
Zak is written in python using the pygtk module. Zak is designed for GNU/Linux, but it is likely possible to get it to work on other systems without too much trouble.
Requires: python, pygtk, gtk+, madplay, and ffmpeg.
Note: This program was inspired by the Windows program "MP3 to iPod Audio Book Converter" available from http://www.freeipodsoftware.com/