A Single-channel Loudness Compensation Method for Digital Hearing Aids Based on Multi-resolution Wavelet

The conventional multi-channel loudness compensation algorithm used in digital hearing aid ignores the protection of speech feature, which results in the deformation of speech structure and low recognition rate. In this paper, a single-channel method based on multi-resolution wavelet is proposed. Multi-resolution wavelet is involved in decomposing and reconstructing the signal, so that the envelope of signal spectrum can be extracted. Then, calculate the required gain of each feature point. After that, the gain of entire signal spectrum is obtained by interpolation algorithm. Experiments show that the proposed algorithm can not only compensate the loudness of speech, but also effectively protect the speech feature, which improves the speech recognition rate.