X265 encoder Latest version:1.3.654 (October 21, 2014)
Supported operating systems:


Windows
All features / Full description:Encoder features
Full prediction and transform quad-tree recursion supported
Adaptive B-frame placement
B-frames as references / arbitrary frame order
CABAC entropy coding
Intra: all block types (32x32, 16x16, 8x8, 4x4, and PCM with all predictions)
Inter P: all partitions (from 64x64 down to 8x4)
Inter B: partitions from 64x64 down to 8x4 (including all merge modes
and biprediction)
Weighted prediction for P slices
Multiple reference frames
Ratecontrol: constant quantizer, constant quality, single pass ABR, optional VBV
Scenecut detection
Parallel encoding on multiple CPUs, both frame-level and wavefront parallelism