Limited Error Based Event Localizing Temporal Decomposition

This paper proposes a low delay temporal decomposition (TD) method for line spectral frequency (LSF) parameters called “Limited Error Based Event Localizing Temporal Decomposition” (LEBEL-TD, for short). In previous work with TD, TD analysis was usually performed on each speech segment of about 200-300 ms or more, making it impractical for online applications. In this present work, the event localization is determined based on a limited error criterion and a local optimization strategy, which results in an average algorithmic delay of 75 ms. Simulation results show that an average log spectral distortion of about 1.5 dB can be achievable at an event rate of 20 events/sec. Also, LEBEL-TD uses neither the computationally costly singular value decomposition routine nor the event refinement process, thus reducing significantly the computational cost of TD. It is shown that excitation information of speech can be well described using the LEBEL-TD technique.