VideoLAN, a project and a non-profit organization.


x264 is a free software library and application for encoding video streams into the H.264/MPEG-4 AVC compression format, and is released under the terms of the GNU GPL.

Download x264 icon Download x264 master  •  Source  •  750kB


Features Overview

  • Provides best-in-class performance, compression, and features.
  • Achieves dramatic performance, encoding 4 or more 1080p streams in realtime on a single consumer-level computer.
  • Gives the best quality, having the most advanced psychovisual optimizations.
  • Support 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 widely used by television broadcasters and ISPs.

Getting x264


The latest x264 source code is available through git repository:

# git clone

You can browse the source on-line.

Application binaries

Official builds for Windows, Linux, and MacOSX are available from here.


2013 August 23 — The x264 Development Newsletter: Volume 39 is out.

2013 July 4 — The x264 Development Newsletter: Volume 38 is out.

2013 May 20 — The x264 Development Newsletter: Volume 37 is out.

2013 May 4 — The x264 Development Newsletter: Volume 36 is out.

Encoder features

  • 8x8 and 4x4 adaptive spatial transform
  • Adaptive B-frame placement
  • B-frames as references / arbitrary frame order
  • CAVLC/CABAC entropy coding
  • Custom quantization matrices
  • Intra: all macroblock types (16x16, 8x8, 4x4, and PCM with all predictions)
  • Inter P: all partitions (from 16x16 down to 4x4)
  • Inter B: partitions from 16x16 down to 8x8 (including skip/direct)
  • Interlacing (MBAFF)
  • Multiple reference frames
  • Ratecontrol: constant quantizer, constant quality, single or multipass ABR, optional VBV
  • Scenecut detection
  • Spatial and temporal direct mode in B-frames, adaptive mode selection
  • Parallel encoding on multiple CPUs
  • Predictive lossless mode
  • Psy optimizations for detail retention (adaptive quantization, psy-RD, psy-trellis)
  • Zones for arbitrarily adjusting bitrate distribution


2010 May 25 — x264 won MSU Sixth MPEG-4 AVC/H.264 Video Codecs Comparison, with ~24% better encoding than second place.

2005 December 26 — x264 won Doom9's 2005 codec shoot-out, passing Ateme by a hair.

2005 December 12 — x264 tied for 1st place (with Ateme) in the second annual MSU MPEG-4 AVC/ H.264 codecs comparison.


For support information and to ask questions, you have the following possibilities:

A mailing list (x264-devel), IRC (#x264@libera and #x264dev@libera) and Issue Tracker.


Please report any bugs on the Issue tracker.

If it is a crash, then compile x264 with ./configure --enable-debug and follow the ffmpeg bugreporting guidelines.


In addition to being free to use under the GNU GPL, x264 is also available under a commercial license. Contact for more details.

Software using x264

If you use x264 in another project, let us know!