A Weighted Log Kurtosis Ratio Measure for Instrumental Musical Tones Assessment in Wideband Speech

Noise distortion in terms of musical tones is one of the most important aspects of instrumental quality assessment of noise reduction systems. While other aspects such as speech component quality and the level of noise attenuation can already be well measured instrumentally by several proposals, instrumental musical tones measurement is still not widely employed. Recently, the log kurtosis ratio has been explored to measure musical tones instrumentally, which leads to a white box test methodology requiring specific information of the particular noise reduction algorithm. Based on our previously published modified log kurtosis ratio measure, in this paper we propose a weighted log kurtosis ratio measure for instrumental musical tones assessment in a black box test manner requiring no knowledge about the noise reduction algorithm. The proposed instrumental measure is verified by a subjective listening test showing an improved overall correlation of |rho|=0.95, and has been proposed as part of an ITU-T Recommendation in Study Group 12, FG CarCOM.