x264 - A free h264/avc encoder.

x264 is a free library for encoding H264/AVC video streams.
The code is written from scratch by Laurent Aimar, Loren Merritt,
Eric Petit (OS X), Min Chen (vfw/asm), Justin Clay (vfw), Måns
Rullgård, Radek Czyz, Christian Heine (asm), Alex Izvorski, and
Alex Wright. It is released under the terms of the GPL license.

Requires yasm available from SlackBuilds.org.