DFKI-LT - Quantifying Quality Degradation of the EVS Super-Wideband Speech Codec
Quantifying Quality Degradation of the EVS Super-Wideband Speech Codec
1 2018 Tenth International Conference on Quality of Multimedia Experience (QoMEX),
Voice transmission networks are commonly planned with the help of computational quality models, which give an estimate of the expected quality that a user will experience. The most popular of these tools is the E-model. When certain parameters are known, such as the applied codec and its bitrate, the model is able to predict the perceived quality of a communication system. Up to now, the E-model is only available for narrowband telephony (300–3400 Hz) and limited also for wideband telephony (100–7000 Hz). With the extension of voice networks to super-wideband telephony (50–14000 Hz), and the introduction of the super-wideband codec EVS to mobile networks and state of the art smartphones, an update of the E-model has become necessary. To this end, we firstly examined the quality improvement of super-wideband over wideband with results from mixed-band listening-only tests, where we found that the quality is improved by 15%. Then, we calculated impairment factors for the EVS codec and analyzed its robustness towards packet loss, by using auditory and instrumental methods.