HandBrake is a “GPL”:Wikipedia:GPL multiplatform, multithreaded video encoder that supports MPEG4, H.264 and DivX (among other things). It used to include DVD ripping, but that is now removed by default (although it will re-use VideoLAN’s code if installed). It was originally available on the BeOS (and still uses the jam build system that was a favorite of many developers for that OS, but now has been ported over to Mac OS X, Windows and Linux).
Here’s an old screenshot:
|May’06||Mac Gems: HandBrake 0.9.0||a HOWTO and presets for common encoding tasks|