Vocoder system and method for vocal sound synthesis

• US 20040260544A1
• Filed: 03/23/2004
• Published: 12/23/2004
• Est. Priority Date: 03/24/2003
• Status: Active Grant

• Current Assignee: Roland Corporation (Taiyo Pacific Partners LP)
• Original Assignee: Roland Corporation (Taiyo Pacific Partners LP)
• Inventors: Kikumoto, Tadao
• Granted Patent: US 7,933,768 B2
• Time in Patent Office: Days
• US Class Current: 704/221
• CPC Class Codes: G10H 1/125 using a digital filter
• CPC Class Codes: G10H 2250/111 Impulse response, i.e. filters defined or specifed by their temporal impulse response features, e.g. for echo or reverberation applications reverberation effects G10H2210/281
• CPC Class Codes: G10H 2250/235 Fourier transform; Discrete Fourier Transform [DFT]; Fast Fourier Transform [FFT]
• CPC Class Codes: G10H 2250/491 Formant interpolation therefor
• CPC Class Codes: G10H 2250/501 Formant frequency shifting, sliding formants wah-wah spectral modulation G10H2210/231
• CPC Class Codes: G10H 5/005 Voice controlled instruments
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: G10L 2021/0135 Voice conversion or morphing
• CPC Class Codes: G10L 25/15 the extracted parameters being formant information

Abstract

A vocoder system for improving the performance expression of an output sound while lightening the computational load. The system includes formant detection means and division means in which the center frequencies have been fixed. The modulation level with which the levels of each of the frequency bands that have been divided in the division means are set by a setting means based on the levels of each of the frequency bands that correspond to those that have been detected in the formant detection means and formant information with which the formants are changed. Therefore, it is possible to improve the performance expression of the output sound with a light computational load and without the need to calculate and change the filter figure of each filter for each sample in order to change the center frequency and bandwidth of each of the filters comprising the division means.

Claims

1. A vocoder system comprising:

formant detection means for detecting formant characteristics of a first musical tone signal;

musical tone signal input means for inputting a second musical tone signal that corresponds to specified pitch information;

division means for dividing the second musical tone signal into a plurality of frequency bands, the respective center frequencies of which have been fixed;

setting means for setting modulation levels corresponding to each of the frequency bands based on the formant characteristics and formant control information with which the formant characteristics detected by the formant detection means are changed; and

modulation means for modulating a level of a signal of each of the frequency bands based on the modulation level set in the setting means.

2. The vocoder system cited in claim 1, wherein the formant detection means comprises a filter.

3. The vocoder system cited in claim 1, wherein the formant detection means comprises a Fourier transform.

4. The vocoder system cited in claim 1, wherein the division means comprises a filter.

5. The vocoder system cited in claim 2, wherein the division means comprises a filter.

6. The vocoder system cited in claim 3, wherein the division means comprises a filter.

7. The vocoder system cited in claim 1, wherein the division means comprises a Fourier transform.

8. The vocoder system cited in claim 2, wherein the division means comprises a Fourier transform.

9. The vocoder system cited in claim 3, wherein the division means comprises a Fourier transform.

10. The vocoder system cited in claim 1, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

11. The vocoder system cited in claim 2, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

12. The vocoder system cited in claim 3, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information

13. The vocoder system cited in claim 4, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

14. The vocoder system cited in claim 5, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

15. The vocoder system cited in claim 6, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

16. The vocoder system cited in claim 7, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

17. The vocoder system cited in claim 8, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

18. The vocoder system cited in claim 9, wherein the setting means sets the modulation levels by interpolation processing based on the formant characteristics and the formant control information.

19. The vocoder system cited in claim 1, wherein the setting means sets the modulation levels based on pitch information, the formant characteristics and the formant control information.

20. The vocoder system cited in claim 2, wherein the setting means sets the modulation levels based on pitch information, the formant characteristics and the formant control information.

21. The vocoder system cited in claim 3, wherein the setting means sets the modulation levels based on pitch information, the formant characteristics and the formant control information.

22. The vocoder system cited in claim 4, wherein the setting means sets the modulation levels based on pitch information, the formant characteristics and the formant control information.

23. The vocoder system cited in claim 5, wherein the setting means sets the modulation levels based on pitch information, the formant characteristics and the formant control information.

24. The vocoder system cited in claim 6, wherein the setting means sets the modulation levels based on musical interval information, the formant characteristics and the formant control information.

25. The vocoder system cited in claim 7, wherein the setting means sets the modulation levels based on musical interval information, the formant characteristics and the formant control information.

26. The vocoder system cited in claim 8, wherein the setting means sets the modulation levels based on musical interval information, the formant characteristics and the formant control information.

27. The vocoder system cited in claim 9, wherein the setting means sets the modulation levels based on musical interval information, the formant characteristics and the formant control information.

28. The vocoder system cited in claim 1, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

29. The vocoder system cited in claim 2, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

30. The vocoder system cited in claim 3, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

31. The vocoder system cited in claim 4, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

32. The vocoder system cited in claim 5, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

33. The vocoder system cited in claim 6, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

34. The vocoder system cited in claim 7, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

35. The vocoder system cited in claim 8, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

36. The vocoder system cited in claim 9, wherein the setting means stores a formant change table that changes the formant non-uniformly and sets the modulation levels that correspond to each of the frequency bands based on the change table.

39. The vocoder system cited in claim 1, wherein the formant detector comprises a filter.

40. The vocoder system cited in claim 1, wherein the formant detector comprises a Fourier transform.

37. A method for generating a musical signal comprising:

detecting formant characteristics of a first musical tone signal;

inputting a second musical tone signal that corresponds to specified pitch information;

dividing the second musical tone signal into a plurality of frequency bands, the respective center frequencies of which have been fixed;

setting modulation levels corresponding to each of the frequency bands based on the formant characteristics and formant control information with which the formant characteristics detected by the formant detection means are changed; and

modulating a level of a signal of each of the frequency bands based on the modulation level set in a setting means.

38. A vocoder system comprising:

a formant detector for detecting formant characteristics of a first musical tone signal;

an input device for inputting a second musical tone signal that corresponds to specified pitch information;

a divider connected to the input device for dividing the second musical tone signal into a plurality of frequency bands, the respective center frequencies of which have been fixed;

a level setter for setting modulation levels corresponding to each of the frequency bands based on the formant characteristics and formant control information with which the formant characteristics detected by the formant detection means are changed; and

a modulator for modulating a level of a signal of each of the frequency bands based on the modulation level set in the level setter.