A recursive parametric spectral subtraction algorithm for speech enhancement

This paper proposes a recursive parametric spectral subtraction (RPSS) algorithm based on the characteristics of the human auditory system to calculate the masking threshold. Since the masking threshold of a clean signal is difficult, if not impossible, to calculate from noisy speech, we add a recursive process to estimate the subtraction factor and the spectral floor factor of parametric spectral subtraction approaches. The recursive process is terminated when the output SNR of the current signal frame shows no further improvement. The effectiveness of the proposed RPSS has been validated by the SNR improvement test and the recognition rate test and compared with the standard power spectral subtraction (PSS) method. According to the experimental results, the proposed method outperforms the PSS method in both tests.