Gain adjusting method and a gain adjusting device

Abstract

A gain adjusting method and a gain adjusting device for adjusting gain of a processed voice signal that is obtained by signal processing an input voice signal are disclosed. According to the gain adjusting method,

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an example of a conventional gain adjusting device;

FIG. 2A and FIG. 2B are waveform charts for explaining the conventional example;

FIG. 3A and FIG. 3B are waveform charts for explaining the conventional example;

FIG. 4 is a block diagram showing the principle of the gain adjusting device according to Embodiment 1 of the present invention;

FIG. 5 is a block diagram of the gain adjusting device according to Embodiment 1 of the present invention;

FIG. 6A and FIG. 6B are waveform charts for explaining the present invention;

FIG. 7A and FIG. 7B are waveform charts for explaining the present invention;

FIG. 8A, FIG. 8B and FIG. 8C are waveform charts for explaining the present invention;

FIG. 9 is a block diagram of the gain adjusting device according to Embodiment 2 of the present invention.

Claims

1. A gain adjusting method of adjusting gain of a processed voice signal obtained by carrying out signal processing on an input voice signal, the processed voice signal being output to a next stage, comprising: a step of computing a masking property of the processed voice signal; anda step of adjusting gain for each frequency of the processed voice signal, the frequency being masked according to the masking property, while a difference between the processed voice signal and the input voice signal is cancelled for a frequency other than the frequency that is masked according to the masking property.

2. The gain adjusting method as claimed in claim 1, wherein the input voice signal and the processed voice signal are in a frequency domain.

3. The gain adjusting method as claimed in claim 2, wherein the step of adjusting the gain adjusts the gain for each frequency band.

4. The gain adjusting method as claimed in claim 2, wherein the step of adjusting the gain adjusts the gain for each frequency spectrum.

5. A gain adjustment device for adjusting gain of a processed voice signal obtained by carrying out signal processing on an input voice signal, the processed voice signal being output to a next stage, comprising: a masking property computing unit for computing a masking property of the processed voice signal; andan adjusting unit for adjusting the gain for each frequency of the processed voice signal, the frequency being masked according to the masking property, while a difference between the processed voice signal and the input voice signal is cancelled for a frequency other than the frequency that is masked according to the masking property.

6. The gain adjusting device as claimed in claim 5, wherein the input voice signal and the processed voice signal are in a frequency domain.

7. The gain adjusting method as claimed in claim 6, wherein the gain adjusting unit adjusts the gain for each frequency band.

8. The gain adjusting method as claimed in claim 6, wherein the gain adjusting unit adjusts the gain for each frequency spectrum.

9. A gain adjusting device, comprising: a first orthogonal transformation unit for carrying out orthogonal transformation of an input voice signal in a time domain to an input voice signal in a frequency domain;a second orthogonal transformation unit for carrying out orthogonal transformation of a processed voice signal, which processed voice signal is obtained by performing signal processing on the input voice signal in the time domain, to a processed voice signal in the frequency domain;a masking property computing unit for computing a masking property of the processed voice signal in the frequency domain;a frequency selecting unit for selecting a frequency that is masked according to the masking property out of the processed voice signal in the frequency domain;a gain determining unit for determining gain for every frequency out of the frequencies selected by the frequency selecting unit, while a difference between the processed voice signal and the input voice signal is cancelled for a frequency other than the frequency that is masked according to the masking property;a gain adjusting unit for adjusting the gain according to the gain determined by the gain determining unit for the frequency that is selected by the frequency selecting unit; anda third orthogonal transformation unit for carrying out orthogonal transformation of the voice signal in the frequency domain, which voice signal is output by the gain adjusting unit, to the voice signal in the time domain, and for outputting the voice signal in the time domain.