A PyCUDA and PP parallelized viterbi decoder.
Pyterbi requires CUDA compute capability of 2.0 or greater.

Pyterbi is about 100 times faster than straight python at decoding a Viterbi trellis of 64 states and 1024 observations.
Pyterbi will provide a roughly linear speedup with the number of processor cores if asked. 

All code and documentation is under an MIT license.