A new error concealment technique for audio transmission with packet loss

We present a new error concealment technique for audio transmission over packet networks with high packet loss rate. Unlike other techniques it modifies the time-scale of correctly received packets instead of repeating them. This is done by a time-domain algorithm, WSOLA, whose parameters are redefined so that short audio segments like lost packets can be extended. Particular attention is paid to the additional delay introduced by the new technique. For subjective hearing tests, single and double packet loss is simulated at high packet loss rates, and the new technique is compared to previous proposals by category judgment and component judgment of sound quality. Mean Opinion Score (MOS) curves show that sound distortions due to packet repetition can be reduced.