Conference Paper

Computing Mel-frequency cepstral coefficients on the power spectrum

Lehrstuhl fur Inf. VI, Rheinisch-Westfalische Tech. Hochschule Aachen
DOI: 10.1109/ICASSP.2001.940770 Conference: Acoustics, Speech, and Signal Processing, 2001. Proceedings. (ICASSP '01). 2001 IEEE International Conference on, Volume: 1
Source: IEEE Xplore

ABSTRACT We present a method to derive Mel-frequency cepstral coefficients
directly from the power spectrum of a speech signal. We show that
omitting the filterbank in signal analysis does not affect the word
error rate. The presented approach simplifies the speech recognizers
front end by merging subsequent signal analysis steps into a single one.
It avoids possible interpolation and discretization problems and results
in a compact implementation. We show that frequency warping schemes like
vocal tract normalization can be integrated easily in our concept
without additional computational efforts. Recognition test results
obtained with the RWTH large vocabulary speech recognition system are
presented for two different corpora: The German VerbMobil II dev99
corpus, and the English North American Business News 94 20k development
corpus

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