Stolcke, A., Chen, B., Franco, H., Gadde, V. R. R., Graciarena, M., Hwang, M. Y., … & Zhu, Q. (2006). Recent innovations in speech-to-text transcription at SRI-ICSI-UW. IEEE Transactions on Audio, Speech, and Language Processing, 14(5), 1729-1744.
We summarize recent progress in automatic speech-to-text transcription at SRI, ICSI, and the University of Washington. The work encompasses all components of speech modeling found in a state-of-the-art recognition system, from acoustic features, to acoustic modeling and adaptation, to language modeling. In the front end, we experimented with nonstandard features, including various measures of voicing, discriminative phone posterior features estimated by multilayer perceptrons, and a novel phone-level macro-averaging for cepstral normalization. Acoustic modeling was improved with combinations of front ends operating at multiple frame rates, as well as by modifications to the standard methods for discriminative Gaussian estimation. We show that acoustic adaptation can be improved by predicting the optimal regression class complexity for a given speaker. […]