OpenH264 是思科公司发布的一个开源的 H.264 编码和解码器。
Constrained Baseline Profile up to Level 5.2 (4096x2304)
Arbitrary resolution, not constrained to multiples of 16x16
Rate control with adaptive quantization, or constant quantization
Slice options: 1 slice per frame, N slices per frame, N macroblocks per slice, or N bytes per slice
Multiple threads automatically used for multiple slices
Temporal scalability up to 4 layers in a dyadic hierarchy
Spatial simulcast up to 4 resolutions from a single input
Long Term Reference (LTR) frames
Memory Management Control Operation (MMCO)
Reference picture list modification
Single reference frame for inter prediction
Multiple reference frames when using LTR and/or 3-4 temporal layers
Periodic and on-demand Instantaneous Decoder Refresh (IDR) frame insertion
Dynamic changes to bit rate, frame rate, and resolution
Annex B byte stream output
YUV 4:2:0 planar input
Single thread for all slices
Multiple reference frames when specified in Sequence Parameter Set (SPS)
Annex B byte stream input
YUV 4:2:0 planar output
Windows 64-bit and 32-bit (initial release is only 32-bit, 64-bit will follow soon)
Mac OS X 64-bit (initial release does not include this target, will follow soon)
Linux 64-bit and 32-bit (initial release is only 32-bit, 64-bit will follow soon)
Android 32-bit (initial release does not include this target, will follow soon)
iOS 64-bit and 32-bit (not supported yet, may be added in the future)
Intel x86 optionally with MMX/SSE (no AVX yet, help is welcome)
ARMv7 optionally with NEON (initial release does not include this target, will follow later)
Any architecture using C/C++ fallback functions
