The blake2 family of hash functions is an improved version of the sha-3 finalist blake.

blake2b is optimized for 64-bit platforms and produces up to 64 bytes of output; blake2s is optimized for 32-bit platforms and produces up to 32 bytes of output.

blake2bp and blake2sp are parallel versions of blake2b and blake2s designed for increased performance on multicore and large-vector simd processors.

libb2 provides a portable implementation of blake2, optimized implementations for ia-32 and amd64 processors, and an interface layer that automatically selects the best implementation for the processor it is run on.