ECHO: A speech recognition package for the design of robust interactive speech-based applications

This paper describes speech recognition software called ECHO (Environnement de Communication Homme-Ordinateur) which is devoted to the design of usable interactive speech-based applications. Usability refers to the stability of the Speech Recognition system performance under ordinary usage conditions (i.e., different acoustic environments) rather than high performance in a limited set of well-known conditions. In order to reach this objective, the system must be able to anticipate any change in the environment and adapt itself to the different usage conditions. One solution for this problem has been achieved by connecting some specialized modules of speech signal pre-processing and post-processing to the automatic speech recognition engine. These different modules interact as a mirror with the speech engine in order to force it to adapt its runtime parameters, thus improving its performance and its robustness.