METHOD AND APPARATUS FOR GENERATING A SPEECH SIGNAL

• US 20150380010A1
• Filed: 02/18/2014
• Published: 12/31/2015
• Est. Priority Date: 02/26/2013
• Status: Active Grant

• Current Assignee: MediaTek, Inc.
• Original Assignee: Koninklijke Philips N.V.
• Inventors: SRINIVASAN, Sriram
• Granted Patent: US 10,032,461 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G10L 2021/02082 the noise being echo, reverberation of the speech
• CPC Class Codes: G10L 2021/02161 Number of inputs available containing the signal or the noise to be suppressed
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: G10L 25/51 for comparison or discrimination
• CPC Class Codes: H04R 1/025 Arrangements for fixing loudspeaker transducers, e.g. in a box, furniture
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 2201/023 Transducers incorporated in garment, rucksacks or the like
• CPC Class Codes: H04R 2420/07 Applications of wireless loudspeakers or wireless microphones
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

An apparatus comprises microphone receivers (101) which receive microphone signals from a plurality of microphones (103). A comparator (105) determines a speech similarity indication indicative of a similarity between the microphone signal and non-reverberant speech for each microphone signal. The determination is in response to a comparison of a property derived from the microphone signal to a reference property for non-reverberant speech. In some embodiments, the comparator (105) determines the similarity indication by comparing to reference properties for speech samples of a set of non-reverberant speech samples. A generator (107) generates a speech signal by combining the microphone signals in response to the similarity indications. In many embodiments, the apparatus may be distributed over a plurality of devices each containing a microphone, and the approach may determine the most suited microphone for generating the speech signal.

Claims

1. An apparatus for generating a speech signal, the apparatus comprising:

microphone receivers for receiving microphone signals from a plurality of microphones;

a comparator arranged to, for each microphone signal, determine a speech similarity indication indicative of a similarity between the microphone signal and non-reverberant speech, the comparator being arranged to determine the similarity indication in response to a comparison of at least one property derived from the microphone signal to at least one reference property for non-reverberant speech; and

a generator for generating the speech signal by combining the microphone signals in response to the similarity indications,

wherein the comparator is further arranged to determine the similarity indication for a first microphone signal in response to a comparison of at least one property derived from the microphone signal to reference properties for speech samples of a set of non-reverberant speech samples.

2. The apparatus of claim 1 comprising a plurality of separate devices, each device comprising a microphone receiver for receiving at least one microphone signal of the plurality of microphone signals.

3. The apparatus of claim 2 wherein at least a first device of the plurality of separate devices comprises a local comparator for determining a first speech similarity indication for the at least one microphone signal of the first device.

4. The apparatus of claim 3 wherein the generator is implemented in a generator device separate from at least the first device;

and wherein the first device comprises a transmitter for transmitting the first speech similarity indication to the generator device.

5. The apparatus of claim 4 wherein the generator device is arranged to receive speech similarity indications from each of the plurality of separate devices, and wherein the generator is arranged to generate the speech signal using a subset of microphone signals from the plurality of separate devices, the subset being determined in response to the speech similarity indications received from the plurality of separate devices.

6. The apparatus of claim 5 wherein at least one device of the plurality of separate devices is arranged to transmit the at least one microphone signal of the at least one device to the generator device only if the at least one microphone signal of the at least one device is comprised in the subset of microphone signals.

7. The apparatus of claim 5 wherein the generator device comprises a selector arranged to determine the subset of microphone signals, and a transmitter for transmitting an indication of the subset to at least one of the plurality of separate devices.

9. The apparatus of claim 1 wherein the speech samples of the set of non-reverberating speech samples are represented by parameters for a non-reverberating speech model.

10. The apparatus of claim 9 wherein the comparator is arranged to determine a first reference property for a first speech sample of the set of non-reverberating speech samples from a speech sample signal generated by evaluating the non-reverberating speech model using the parameters for the first speech sample, and to determine the similarity indication for a first microphone signal of the plurality of microphone signals in response to a comparison of the property derived from the first microphone signal and the first reference property.

11. The apparatus of claim 1 wherein the comparator is arranged to decompose a first microphone signal of the plurality of microphone signals into a set of basis signal vectors;

and to determine the similarity indication in response to a property of the set of basis signal vectors.

12. The apparatus of claim 1 wherein the comparator is arranged to determine speech similarity indications for each segment of a plurality of segments of the speech signal, and the generator is arranged to determine combination parameters for the combining for each segment.

13. The apparatus of claim 10 wherein the generator is arranged to determine combination parameters for one segment in response to similarity indications of at least one previous segment.

14. The apparatus of claim 1 wherein the generator is arranged to select a subset of the microphone signals to combine in response to the similarity indications.

8. (canceled)

15. A method of generating a speech signal, the method comprising:

receiving microphone signals from a plurality of microphones;

for each microphone signal, determining a speech similarity indication indicative of a similarity between the microphone signal and non-reverberant speech, the similarity indication being determined in response to a comparison of at least one property derived from the microphone signal to at least one reference property for non-reverberant speech; and

generating the speech signal by combining the microphone signals in response to the similarity indications,

wherein the similarity indication is further determined for a first microphone signal in response to a comparison of at least one property derived from the microphone signal to reference properties for speech samples of a set of non-reverberant speech samples.