Internal Program Version:  x264 120  (The HEADER-Files)

x264 is a free library for encoding next-generation
H264/AVC video streams.

Encoder features:
- 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: constant quantizer, single or multipass ABR, optional VBV
- 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

http://developers.videolan.org/x264.html