Validation of the Non-Intrusive Codebook-Based Short Time Objective Intelligibility Metric for Processed Speech
Charlotte Sørensen, Jesper Bunsow Boldt, Mads Græsbøll Christensen · 2019
In recent years, objective measures of speech intelligibility have gained increasing interest. However, most speech intelligibil- ity metrics require a clean reference signal, which is often not available in real-life applications. In a recent publication, we proposed a method, the Non-Intrusive Codebook-based Short- Time Objective Intelligibility (NIC-STOI) metric, which allows using an intrusive method without requiring access to the clean signal. The statistics of the reference signal is estimated as a combination of predefined codebooks that best fit the degraded signal by modeling the speech and noisy spectra. In this pa- per, we perform additional validation of the NIC-STOI in more diverse noise condition as well as for speech processed non- linearly with binary masks, where it is shown to outperform existing non-intrusive metrics.