Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks.

It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs.

Tasks can be automated using projects, job queue and powerful scripting capabilities.Avidemux is available for Linux, BSD, Mac OS X and Microsoft Windows under the GNU GPL license.

Get it here: Avidemux