  In this paper, we present an update to the NISQA speech quality prediction
model that is focused on distortions that occur in communication networks. In
contrast to the previous version, the model is trained end-to-end and the
time-dependency modelling and time-pooling is achieved through a Self-Attention
mechanism. Besides overall speech quality, the model also predicts the four
speech quality dimensions Noisiness, Coloration, Discontinuity, and Loudness,
and in this way gives more insight into the cause of a quality degradation.
Furthermore, new datasets with over 13,000 speech files were created for
training and validation of the model. The model was finally tested on a new,
live-talking test dataset that contains recordings of real telephone calls.
Overall, NISQA was trained and evaluated on 81 datasets from different sources
and showed to provide reliable predictions also for unknown speech samples. The
code, model weights, and datasets are open-sourced.
