In this paper, we investigate a new method for extracting useful information from the group delay spectrum of speech. The group delay spectrum is often poorly behaved and noisy. In the literature, various methods have been proposed to address this problem. However, to make the group delay a more tractable function, these methods have typically relied upon some modification of the underlying spe...

This paper presents an efficient low-delay CELP speech coder based on a structure given by Chen et el. [1]. The proposed coder can operate at a rate of 8 Kb/s and has an arithmetic complexity that is 20% lower than that of the CELP of [1] with an acceptable increase in the delay. The proposed coder has been tested to provide a good-quality speech.

This paper investigates the significance of combining cepstral features derived from the modified group delay function and from the short-time spectral magnitude like the MFCC. The conventional group delay function fails to capture the resonant structure and the dynamic range of the speech spectrum primarily due to pitch periodicity effects. The group delay function is modified to suppress thes...

This paper analyzes the relationship between transmission delay, conversational interactivity and perceived quality of bidirectional speech. Our work is grounded on the results of subjective speech quality tests conducted in our lab and recent studies in this field. The test experiments do not only quantify the impact of network delay on speech quality as perceived by untrained subjects. They a...