Integrated speech enhancement and coding in the time-frequency domain

This paper addresses the problem of merging speech enhancement and coding in the context of an auditory modeling. The noisy signal is first processed by a fast wavelet packet transform algorithm to obtain an auditory spectrum, from which a rough masking model is estimated. Then, this model is used to refine a subtractive-type enhancement algorithm. The enhanced speech coefficients are then encoded in the same time-frequency transform domain using masking threshold constraints for quantization noise. The advantage of the proposed method is that both enhancement and coding are performed with the transform coefficients, without making use of the additional FFT processing