Principes et performances du décodeur parole continue Speeral

This paper presents the continuous speech recognition system Speeral developed in the LIA. Speeral uses a modified A* algorithm to find in the search graph the best path taking into account acoustic and linguistic constraints. Rather than words by words, the A* used in Speeral is based on a phoneme lattice previously generated. To avoid the backtraking problems, the system keeps for each frame the deepest nodes of the lexical tree (partially explored) starting at this frame. If a new hypothesis to explore is ended by a word and the lexicon starting where this word finishes has already been developed, then the next hypothesis will ''jump'' directly to the deepest nodes.