Automatic generation of lexical and grammatical constraints for speech recognition

A compiler for constructing optimized syntactic digraphs from easily written grammar specifications is described. These are written in a language called GSL (grammar specification language). The compiler has a preprocessing (macro expansion) phase, a parse phase, graph code generation and compilation phases, and two optimization phases. Digraphs can also be linked together by a graph linker to form larger digraphs. Language complexity is analyzed in a statistics phase. The grammar specification language has been used by several untutored users with good success. It is demonstrated that the optimization phase yields graphs with even greater efficiency than previously achieved by hand. Results of applying these techniques to intermediate and large digraphs are also discussed