Adaptive delay concealment for Internet voice applications with packet-based time-scale modification

Abstract

Much effort has been involved in packet-level error control and delay jitter concealment for Internet audio applications. A packet-based time-scale modification scheme for speech signals is developed to provide adaptive delay concealment, at the receiver for an Internet voice session in this work. The adaptive playout algorithm strives to minimize packet droppings for late-arrival packets and premature packets while maintaining the end-to-end delay constraint. By stretching the length of voice segments and incorporating silence intervals, the proposed algorithm is able to accommodate fluctuating delays including delay spikes quickly. It is verified by experiments that the proposed adaptive playout algorithm improves the received speech intelligence under a tightly bounded average playout delay.