Discomfort Reduction Based on Time-Frequency Auditory-Masking for Railway Brake Sound

Railway brake sound is loud emitted in the station yard in using outmoded passenger cars. The sound has continuous and non-stationary spectral peaks and gives the passengers discomfort feelings. We have previously proposed a discomfort reduction based on auditory masking. Discomfort reduction is realized for the stationary noise with spectral peaks by emitting the auditory masker, which masks spectral peaks in higher frequency band. However, it is difficult to introduce the previously proposed method into the railway brake sound because the railway brake sound is the noise with continuous and non-stationary spectral peaks. Therefore, in this paper, we propose a new discomfort reduction based on time-frequency auditory-masking for the railway brake sound. The proposed method estimates spectral peaks of the railway brake frame by frame. Estimated spectral peaks are masked by the auditory masker, which is designed based on the shape of auditory filter bank. The proposed method can minimize the power of the auditory masker because auditory filter bank has characteristics suitable to the human auditory. Finally, we carried out an evaluation experiment and confirmed the effectiveness of the proposed method.