Spectral Dynamics for Speech Recognition Under Adverse Conditions

Significant improvements in automatic speech recognition performance have been obtained through front-end feature representations which exploit the time varying properties of speech spectra. Various techniques have been developed to incorporate “spectral dynamics” into the speech representation, including temporal derivative features, spectral mean normalization and, more generally, spectral parameter filtering. This chapter describes the implementation and interrelationships of these techniques and illustrates their use in automatic speech recognition under different types of adverse conditions.