x264 is a free software library and application for encoding video streams into the H.264/MPEG-4 AVC format, and is released under the terms of the GNU GPL. The code is written from scratch by Laurent Aimar, Loren Merritt, Eric Petit (OS X), Min Chen (vfw/asm), Justin Clay (vfw), Mans Rullgard, Radek Czyz, Christian Heine (asm), Alex Izvorski, Alex Wright and Jason Garrett-Glaser.
It provides best-in-class performance, compression, and features. Performance-wise, x264 can encode 4 or more 1080p streams in realtime on a single consumer-level computer. Quality-wise, x264 has the world's most advanced psychovisual optimizations and has won many awards, . Feature-wise, x264 supports features necessary for many different applications, such as television broadcast, Blu-ray, low-latency video applications, and web video. x264 forms the core of many web video services, such as Youtube, Facebook, Vimeo, and Hulu. It is also used in television broadcast by companies such as Avail Media.

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