x264 é uma biblioteca gratuita para codificação de streams de video H264/AVC. Todo o código foi escrito a partir de zero por Laurent Aimar, Loren Merritt, Eric Petit(OS X), Min Chen (vfw/asm), Justin Clay(vfw), Måns Rullgård, Christian Heine (asm), and Alex Izvorski (asm).

Pontos-chave do x264:

· CAVLC/CABAC
· Multi-references
· Intra: all macroblock types (16x16, 8x8, and 4x4 with all predictions)
· Inter P: all partitions (from 16x16 down to 4x4)
· Inter B: partitions from 16x16 down to 8x8 (including skip/direct)
· Ratecontrol: optional VBV, single or multipass ABR, constant quantizer
· Scene cut detection
· Adaptive B-frame placement
· B-frames as references / arbitrary frame order
· 8x8 and 4x4 adaptive spatial transform
· Lossless mode
· Custom quantization matrices
· Parallel encoding of multiple slices


Nota: x264 é considerado ALPHA, logo poderá encontrar alguns erros!