Axiom is a GUI for FFmpeg, a command line tool to convert multimedia files between formats.
FFmpeg is not for those who don't like the command prompt and switches. While it's a great app, there's just so many possible switches that we've always avoided it - until now. What Axiom does is generate command scripts that FFmpeg can interpret and process.
Axiom makes it simple to use all of the features available. Browse to the file you want to open and choose where to output it. Drop down boxes give you quick access all the preset formats, video, audio, channel, resize, cut, and more. Under each of those drop-down boxes are other options so that you can work from left to right and get everything how you like it and convert. Optionally, you can play the converted file to make sure you're happy.
Axiom is the missing link for anyone who was told about FFmpeg and ran away when they realized it was a command-line tool.
For those who don't have FFmpeg, MajorGeeks mirrors have it included to save you the trouble of downloading both.