Mei-Yuh Hwang, Gang Peng, Wen Wang, A. Faria, A. Heidel and M. Ostendorf, “Building a highly accurate Mandarin speech recognizer,” 2007 IEEE Workshop on Automatic Speech Recognition & Understanding (ASRU), 2007, pp. 490-495, doi: 10.1109/ASRU.2007.4430161.
We describe a highly accurate large-vocabulary continuous Mandarin speech recognizer, a collaborative effort among four research organizations. Particularly, we build two acoustic models (AMs) with significant differences but with similar accuracy for the purposes of cross adaptation and system combination. This paper elaborates on the main differences between the two systems, where one recognizer incorporates a discriminatively trained feature while the other utilizes a discriminative feature transformation. Additionally we present an improved acoustic segmentation algorithm and topic-based language model (LM) adaptation. Coupled with increased acoustic training data, we reduced the character error rate (CER) of the DARPA GALE 2006 evaluation set to 15.3% from 18.4%.