MetricGAN+: An Improved Version of MetricGAN for Speech Enhancement
Szu‐Wei Fu, Cheng Yu, Tsun-An Hsieh, Peter Plantinga, Mirco Ravanelli, Xugang Lu, Yu Tsao
Abstract
The discrepancy between the cost function used for training a speech enhancement model and human auditory perception usually makes the quality of enhanced speech unsatisfactory.Objective evaluation metrics which consider human perception can hence serve as a bridge to reduce the gap.Our previously proposed MetricGAN was designed to optimize objective metrics by connecting the metric with a discriminator.Because only the scores of the target evaluation functions are needed during training, the metrics can even be non-differentiable.In this study, we propose a MetricGAN+ in which three training techniques incorporating domainknowledge of speech processing are proposed.With these techniques, experimental results on the VoiceBank-DEMAND dataset show that MetricGAN+ can increase PESQ score by 0.3 compared to the previous MetricGAN and achieve stateof-the-art results (PESQ score = 3.15).