The General Hidden Markov Model library (GHMM) is a freely available LGPL-ed C library implementing efficient data structures and algorithms for basic and extended HMMs. The development is hosted at Sourceforge http://sourceforge.net/projects/ghmm/,

PORUS is a portable USB device stack. It is designed to contain, as far as possible, all of the code common to a complete USB device implementation. PORUS is neither stable nor finished. Until version 1.0.0, the API may change, perhaps sign