NETWORK AUDIO PROCESSOR

• US 20100142716A1
• Filed: 07/17/2008
• Published: 06/10/2010
• Est. Priority Date: 08/16/2007
• Status: Active Grant

• Current Assignee: InterDigital CE Patent Holdings SAS (InterDigital, Inc.)
• Original Assignee: Thomson Licensing LLC (The Woodbridge Co. Ltd.)
• Inventors: Harris, Ken, Lee, Bret Evan
• Granted Patent: US 8,755,532 B2
• Time in Patent Office: Days
• US Class Current: 381/57
• CPC Class Codes: G10L 21/0264 characterised by the type of parameter measurement, e.g. correlation techniques, zero crossing techniques or predictive techniques
• CPC Class Codes: G10L 21/0364 for improving intelligibility
• CPC Class Codes: H04R 2227/001 Adaptation of signal processing in PA systems in dependence of presence of noise
• CPC Class Codes: H04R 2227/003 Digital PA systems using, e.g. LAN or internet
• CPC Class Codes: H04R 2430/03 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04R 27/00 Public address systems circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; monitoring or testing arrangements for public address systems H04R29/007; amplifiers H03F

Abstract

An audio circuit and associated method for enhanced intelligibility of audio content includes a first means for receiving reproduced audio content, a microphone for providing a microphone output signal in accordance with ambient noise, a second means for enabling the microphone output signal when the reproduced audio content is off, and disabling the microphone output signal when the reproduced audio content is on, and a signal processor, in communication with the first and second means. The signal processor applies a transfer function to the reproduced audio content for increasing gain to the reproduced audio content as a function of increasing amplitude of the microphone output signal, and decreasing gain to the reproduced audio content signal as a function of decreasing amplitude of the microphone output signal, and applies an equalization curve to the audio content to boost frequencies in a range that enhances consonant perception thus increasing speech intelligibility.

Claims

1. A network audio processing circuit, comprising:

a first means for receiving a reproduced audio content signal;

a microphone for providing a microphone output signal in accordance with ambient noise;

a second means for enabling the microphone output signal during first increments of time when the reproduced audio content signal is substantially off, and disabling the microphone output signal during second increments of time when the reproduced audio content signal is on; and

a signal processor, in communication with the first and second means for;

applying a transfer function to the reproduced audio content signal, the transfer function incrementally increasing gain adjustments to the reproduced audio content signal as a function of an increasing amplitude of the microphone output signal, and incrementally decreasing gain adjustments to the reproduced audio content signal as a function of a decreasing amplitude of the microphone output signal; and

applying an equalization curve to the audio content signal to boost frequencies in a vocal range that enhance consonant perception thus increasing speech intelligibility.

2. The network audio processing circuit of claim 1, wherein said signal processor further applies a delay to the audio content signal.

3. The network audio processing circuit of claim 2, wherein said delayed audio content signal is perceived to be emanating from a content playout device associated with said audio content signal instead of from a speaker on which said audio processing circuit is integrated.

4. The network audio processing circuit of claim 1, further comprising at least one amplifier having an input and an output, the amplifier input coupled to the output signal of the signal processor and the amplifier output coupled to an input of a speaker.

5. The network audio processing circuit of claim 4, wherein the signal processor communicates with the at least one amplifier to determine if a respective speaker is connected to the network audio processing circuit or if the respective speaker is failing to operate properly.

6. A method of enhanced intelligibility of a reproduced audio content signal in the presence of ambient noise, comprising the steps of:

receiving the reproduced audio content signal;

monitoring ambient noise signals using a microphone to provide a microphone output signal;

enabling the microphone output signal during first increments of time when the reproduced audio content signal is substantially off, and disabling the microphone output signal during second increments of time when the reproduced audio content signal is on, such that the microphone output signal includes ambient noise signal components without including reproduced content signal components;

applying a first transfer function to the reproduced audio content signal, the first transfer function incrementally increasing gain adjustments to the reproduced audio content signal as a function of an increasing amplitude of the microphone output signal, and incrementally decreasing gain adjustments to the reproduced audio content signal as a function of a decreasing amplitude of the microphone output signal; and

applying an equalization curve to the audio content signal to boost frequencies in a vocal range that enhance consonant perception thus increasing speech intelligibility.

7. The method of claim 6, wherein the incremental gain adjustments are in steps of between about 1 dB and about 10 dB.

8. The method of claim 6, comprising applying a delay to the audio content signal.

9. The method of claim 6, comprising initiating a query to determine if a respective speaker is connected or if the respective speaker is failing to operate properly.