PERCEPTUAL AUDIO QUALITY ANALYSIS OF VOIP LOSS-RECOVERY TECHNIQUES

摘要

Voice over Internet Protocol (VoIP) is a technology that transports voice data packets across packet-switched networks using the Internet Protocol (IP). Losing packets in the network is inevitable, and losing voice packets degrades audio quality. There are many loss-recovery techniques that designers can use to mitigate the undesired effects of packet loss. Some of these loss-recovery techniques use sender-based procedures, and others use receiver-based procedures. We examine several well-known sender-based loss-recovery techniques that are feasible for real-time interactive VoIP applications. We analyze the bandwidth requirements and buffering delays of these techniques. Additionally, we evaluate the perceptual sound quality of these approaches under a simulated real-network loss condition. We also compare the effectiveness of these techniques against a speech coder that has high degree of packet-loss robustness.