METHOD AND APPARATUS FOR SPEECH RECONSTRUCTION IN A DISTRIBUTED SPEECH RECOGNITION SYSTEM

摘要

A method of reconstructing speech input at a communication device comprises receiving, at the communication device, encoded data that includes encoded spectral data and encoded energy data of the speech input, the encoded spectral data being encoded as a series of mel-frequency cepstral coefficients. The method further comprises decoding, at the communication device, the encoded spectral data and encoded energy data to determine the spectral data and energy data, wherein decoding comprises: performing an inverse discrete cosine transform on the mel-frequency cepstral coefficients at harmonic mel-frequencies corresponding to a pitch period of the speech input to determine log-spectral magnitudes of the speech input at the harmonic mel-frequencies, and exponentiating the log-spectral magnitudes to determine the spectral magnitudes of the speech input. The method also comprises combining the spectral data and energy data to reconstruct the speech input at the communication device. A communication device for use in distributed speech recognition system is also disclosed.