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, Alex Wright and Jason Garrett-Glaser.
It is released under the terms of the GNU GPL.
-Development status
-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.
