JANUS-II: towards spontaneous Spanish speech recognition

JANUS-II is a research system for investigating various issues in speech-to-speech translations and has been implemented for translations in many languages. In this paper, we address the Spanish speech recognition part of JANUS-II. First, we report the bootstrapping and optimization of the recognition system. Then we investigate the difference between push-to-talk and cross-talk dialogs, which are two different kinds of data in our database. We give a detailed noise analysis for the push-to-talk and cross-talk dialogs and present some recognition results for comparison. We have observed that the cross-talk dialogs are harder than the push-to-talk dialogs for speech recognition, because they are more noisy than the latter. Currently, the error rate of our Spanish recognizer is 27% for the push-to-talk test set and 32% for the cross-talk test set.