x264 is an advanced commandline encoder for creating H.264 (MPEG-4 AVC)
 video streams.
 .
 x264 supports the following features:
  * CABAC (context-based adaptive binary arithmetic coding) and CAVLC
    (context-based adaptive variable length coding
  * multiple reference frames
  * 16x16, 8x8 and 4x4 intra-predicted macroblocks
  * all P-frame inter-predicted macroblock types
  * B-Inter-predicted macroblock types from 16x16 down to 8x8
  * rate distortion optimization
  * multiple rate control modes (constant quantizer, constant quality, single
    or multipass ABR with the option of VBV)
  * scene cut detection
  * adaptive B-frame placement, with the option of keeping B-frames as
    references / arbitrary frame order
  * 8x8 and 4x4 adaptive spatial transform (high profile)
  * lossless mode (high 4:4:4 profile)
  * custom quantization matrices (high profile)
  * parallel encoding on multiple CPUs
  * interlaced streams