Signal processing apparatus and mobile radio communication terminal

• US 7,058,574 B2
• Filed: 12/01/2004
• Issued: 06/06/2006
• Est. Priority Date: 05/10/2000
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Miseki, Kimio, Taniguchi, Takayuki, Tsukahara, Yuriko
• Primary Examiner(s): MCFADDEN, SUSAN IRIS
• Application Number:
  US11/000,268
• Publication Number:
  US 20050096904A1
• Time in Patent Office: 552 Days
• Field of Search: None
• US Class Current: 704/233
• CPC Class Codes: G10L 19/18 Vocoders using multiple modes
• CPC Class Codes: G10L 21/0208 Noise filtering

Abstract

In a signal processing apparatus, a speech coder includes, as three sections for coding speech data by different algorithm, an Algorithm-A coding section, an Algorithm-B coding section and an Algorithm-C coding section. A noise suppressor includes, as three sections for suppressing background noise by different algorithm, an Algorithm-X noise suppress section, an Algorithm-Y noise suppress section and an Algorithm-Z noise suppress section. A suppress algorithm switching control section controls switching on the basis of information from a coding algorithm switching control section such that an optimal one of the noise suppress sections may function in association with the coding section activated in the speech coder.

Claims

1. A signal processing apparatus comprising:

a noise suppressor having a plurality of different noise suppression characteristics for suppressing background noise contained in a speech signal, where a number of the noise suppression characteristics is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

Q>

1);

means for selecting one of the plurality of noise suppression characteristics and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression characteristic and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

2. The signal processing apparatus according to claim 1, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

3. A signal processing apparatus comprising:

a noise suppressor having a plurality of different noise suppression characteristics for suppressing background noise contained in a speech signal, where a number of the noise suppression characteristics is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

Q>

1);

means for selecting one of the plurality of noise suppression characteristics and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression characteristic and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

4. A signal processing apparatus comprising:

a parameter table configured to store a plurality of parameter sets for characterizing a noise suppressor, where a number of the parameter sets is S (S;

a positive integer);

a noise suppressor, whose noise suppression characteristic is varied in accordance with the parameter set, configured to suppress background noise contained in a speech signal;

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

S>

1);

means for selecting one of the plurality of parameter sets and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the noise suppression characteristic in accordance with the selected parameter set and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

5. The signal processing apparatus according to claim 4, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

6. A signal processing apparatus comprising:

a parameter table configured to store a plurality of parameter sets for characterizing a noise suppressor, where a number of the parameter sets is S (S;

a positive integer);

a noise suppressor, whose noise suppression characteristic is varied in accordance with the parameter set, configured to suppress background noise contained in a speech signal;

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

S>

1);

means for selecting one of the plurality of parameter sets and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the noise suppression characteristic in accordance with the selected parameter set and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

7. A signal processing apparatus comprising:

a noise suppressor having a plurality of different noise suppression algorithms for suppressing background noise contained in a speech signal, where a number of the noise suppression algorithms is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

Q>

1);

means for selecting one of the plurality of noise suppression algorithms and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression algorithm and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

8. The signal processing apparatus according to claim 7, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

9. A signal processing apparatus comprising:

a noise suppressor having a plurality of different noise suppression algorithms for suppressing background noise contained in a speech signal, where a number of the noise suppression algorithms is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

Q>

1);

means for selecting one of the plurality of noise suppression algorithms and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression algorithm and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

10. A mobile communication terminal having a signal processor, the signal processor comprising:

a microphone configured to capture a speech signal;

a noise suppressor having a plurality of different noise suppression characteristics for suppressing background noise contained in the speech signal, where a number of the noise suppression characteristics is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

Q>

1);

means for selecting one of the plurality of noise suppression characteristics and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression characteristic and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

18. The mobile communication terminal according to claim 10, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

11. A mobile communication comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a noise suppressor having a plurality of different noise suppression characteristics for suppressing background noise contained in the speech signal, where a number of the noise suppression characteristics is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

Q>

1);

means for selecting one of the plurality of noise suppression characteristics and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression characteristic and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

12. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a parameter table configured to store a plurality of parameter sets for characterizing a noise suppressor, where a number of the parameter sets is S (S;

a positive integer);

a noise suppressor, whose noise suppression characteristic is varied in accordance with the parameter set, configured to suppress background noise contained in the speech signal;

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

S>

1);

means for selecting one of the plurality of parameter sets and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the noise suppression characteristic in accordance with the selected parameter set and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

13. The mobile communication terminal according to claim 12, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

14. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a parameter table configured to store a plurality of parameter sets for characterizing a noise suppressor, where a number of the parameter sets is S (S;

a positive integer);

a noise suppressor, whose noise suppression characteristic is varied in accordance with the parameter set, configured to suppress background noise contained in the speech signal;

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

S>

1);

means for selecting one of the plurality of parameter sets and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the noise suppression characteristic in accordance with the selected parameter set and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

15. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a noise suppressor having a plurality of different noise suppression algorithms for suppressing background noise contained in the speech signal, where a number of the noise suppression algorithms is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding algorithms for encoding an output signal from the noise suppressor, where a number of the speech coding algorithms is P (P;

positive integer and P≧

Q>

1);

means for selecting one of the plurality of noise suppression algorithms and one of the plurality of speech coding algorithms based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression algorithm and the speech encoder with the selected speech coding algorithm,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

16. The mobile communication terminal according to claim 15, wherein one of the speech coding algorithms is the AMR standard or the EVRC standard.

17. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a noise suppressor having a plurality of different noise suppression algorithms for suppressing background noise contained in the speech signal, where a number of the noise suppression algorithms is Q (Q;

a positive integer);

a speech encoder having a plurality of different speech coding rates for encoding an output signal from the noise suppressor, where a number of the speech coding rates is R (R;

positive integer and R≧

Q>

1);

means for selecting one of the plurality of noise suppression algorithms and one of the plurality of speech coding rates based upon a select command; and

control means for activating the noise suppressor with the selected noise suppression algorithm and the speech encoder with the selected speech coding rate,

wherein the speech signal is encoded by using the noise suppressor and the speech encoder activated by the control means.

19. A signal processing apparatus comprising:

a plurality of noise suppressors;

a plurality of speech encoders; and

means for selecting one of the plurality of noise suppressors and one of the plurality of speech encoders,

wherein a background noise contained in an input speech signal is suppressed by using the selected noise suppressor and an output signal from the noise suppressor is encoded using the selected speech encoder.

20. The signal processing apparatus according to claim 19, wherein at least two of the plurality of the noise suppressors have noise suppression characteristics different from each other and at least two of the plurality of the speech encoders have speech coding algorithms different from each other.

21. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a plurality of noise suppressors;

a plurality of speech encoders; and

means for selecting one of the plurality of noise suppressors and one of the plurality of speech encoders,

wherein a background noise contained in the speech signal is suppressed by using the selected noise suppressor and an output signal from the noise suppressor is encoded using the selected speech encoder.

22. The mobile communication terminal according to claim 21, wherein at least two of the plurality of the noise suppressors have noise suppression characteristics different from each other and at least two of the plurality of the speech encoders have speech coding algorithms different from each other.

23. A signal processing apparatus comprising:

a plurality of noise suppressor programs;

a plurality of speech encoder programs;

means for selecting one of the plurality of noise suppressor programs and one of the plurality of speech encoder programs;

means for suppressing a background noise contained in a speech signal by using the selected noise suppressor program; and

means for encoding an output signal from the noise suppression means by using the selected speech encoder program.

24. A mobile communication terminal comprising:

a signal processor, the signal processor comprising;

a microphone configured to capture a speech signal;

a plurality of noise suppressor programs;

a plurality of speech encoder programs;

means for selecting one of the plurality of noise suppressor programs and one of the plurality of speech encoder programs;

means for suppressing a background noise contained in a speech signal by using the selected noise suppressor program; and

means for encoding an output signal from the noise suppression means by using the selected speech encoder program.

25. A signal processing apparatus comprising:

a plurality of speech decoders;

a plurality of noise suppressors; and

means for selecting one of the plurality of speech decoders and one of the plurality of noise suppressors,

wherein a speech signal is decoded by using the selected speech decoder and a background noise contained in the speech signal is suppressed by using the selected noise suppressor.

26. A signal processing apparatus comprising:

a plurality of speech decoder programs;

a plurality of noise suppressor programs;

means for selecting one of the plurality of speech decoder programs and one of the plurality of noise suppressor programs;

means for decoding a speech signal by using the selected speech decoder program; and

means for suppressing a background noise contained in the speech signal by using the selected noise suppressor program.