Short- and Long-Term Packet Loss Behavior: Towards Speech Quality Prediction for Arbitrary Loss Distributions

A speech-quality-oriented classification of packet loss distributions is proposed according to both the short- and long-term loss behavior. While the short-term behavior (microscopic loss behavior) relates to the effect of packet loss on the coder and packet loss concealment performance, the long-term loss behavior (macroscopic loss behavior) is defined so that it reflects the loss behavior that ultimately leads to speech quality that perceptively changes over time. Based on this classification, different parametric (objective) modeling approaches for predicting speech quality are discussed. To this aim, a packet loss averaging approach is presented for modeling speech quality under short-term loss. Starting from this model, two different ways for predicting speech quality under long-term-dependent packet loss are analyzed and compared to auditory (subjective) test results: quality prediction based on the averaging at packet trace level as provided, for example, by the E-model (2005), and the prediction based on the time-averaging of estimated instantaneous quality profiles, as suggested, for example, by L. Gros and N. Chateau (2001) (1998). From this comparison, the suitability of the different approaches for network planning are discussed, and their limitations in case of particular loss distributions are pointed out