| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the service quality by accurately cancelling the noise component included in a voice signal. SOLUTION: A noise frame is orthogonally converted by an FFT fast Fourier transform) 103, and its conversion coefficients are divided into N groups by a group-classified fundamental reduction value determining part 104, and the average value of conversion coefficients in each group is compared with a threshold, and the fundamental reduction value is determined in accordance with the comparison result. Conversion coefficients outputted from the FFT 103 are suppressed in a conversion coefficient suppression part 105 based on this fundamental reduction value.</p> |
