Comparison and optimization of packet loss recovery methods based on AMR-WB for VoIP

AMR-WB codec, which has been standardized for wideband speech conversational applications, has a broad range of potential applications in the migration of wireless and wireline networks towards a single converged IP network. Forward error control (FEC) and multiple description coding (MDC) are two promising techniques to make the transmission robust against packet loss in Voice over IP (VoIP). However, how to achieve the optimal reconstructed speech quality with these methods for AMR-WB under different packet loss rate conditions is still an open problem. In this paper, we compare the performance of various FEC and MDC schemes for the AMR-WB codec both analytically and experimentally. Based on the comparison results, some advantageous configurations of FEC and MDC for the AMR-WB codec are obtained, and hence an optimization system is proposed by selecting the optimal packet loss recovery scheme in accordance with the variable network conditions. Subjective AB test results show that the optimization can lead to obvious improvements of the perceived speech quality in the IP environment.