METHOD AND SYSTEM FOR DIGITAL GAIN PROCESSING IN A HARDWARE AUDIO CODEC FOR AUDIO TRANSMISSION

• US 20100057474A1
• Filed: 10/09/2008
• Published: 03/04/2010
• Est. Priority Date: 06/19/2008
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Kong, Hongwei
• Granted Patent: US 9,378,751 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G10L 19/22 Mode decision, i.e. based on audio signal content versus external parameters
• CPC Class Codes: G10L 21/00 Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility G10L19/00 takes precedence

Abstract

In a hardware audio CODEC which processes audio signals from a plurality of inputs, voltage and/or power levels of the input audio signals may be adjusted such that the digitally adjusted levels are approximately equal for each of the plurality of inputs. The digital adjustment may comprise, for each audio sample of one of the input audio signals, adding the audio sample to one or more right shifted versions of the audio sample and selecting a portion of a summed audio signal resulting from the addition. The portion of the summed audio that is selected may be determined based on the type of audio content being processed. The one or more right shifted versions of the audio sample may be selected via one or more switching elements which may be controlled via a digital control word which may be dynamically generated.

Claims

1. A method for processing audio signals, the method comprising:

in a hardware audio CODEC which processes audio signals from a plurality of inputs, digitally adjusting levels of said input audio signals such that said digitally adjusted levels are approximately equal for each of said plurality of inputs, wherein said digitally adjusting comprises;

for each audio sample of one of said input audio signals, adding said audio sample to one or more right shifted versions of said audio sample; and

selecting a portion of a summed audio signal resulting from said addition.

2. The method according to claim 1, wherein said plurality of inputs comprise one or more analog microphones.

3. The method according to claim 1, wherein said plurality of inputs comprise one or more digital microphones.

4. The method according to claim 1, comprising shifting each of said one or more right shifted versions of said audio sample by a different number of bits.

5. The method according to claim 1, comprising coarsely adjusting said levels of said input audio signals in 6 dB steps via said selecting said portion of said summed audio signal.

6. The method according to claim 1, comprising finely adjusting a gain applied to said audio sample, via said adding said audio sample to one or more right shifted versions of said audio sample, to be between a value of 1 and 2.

7. The method according to claim 1, comprising selecting said portion of said summed audio signal based on a type of audio content being processed.

8. The method according to claim 7, wherein said type of audio content is one or more of voice, music, and ringtone.

9. The method according to claim 1, comprising selecting which of said one or more right shifted versions of said audio sample are added to said audio sample via one or more switching elements.

10. The method according to claim 9, comprising controlling said one or more switching elements via a digital control word.

11. The method according to claim 10, wherein said digital control word is dynamically generated.

12. A system for processing audio signals, the system comprising:

one or more circuits for use in a hardware audio CODEC that processes audio signals from a plurality of inputs, wherein;

said one or more circuits are operable to digitally adjust levels of said input audio signals such that said digitally adjusted levels are approximately equal for each of said plurality of inputs, wherein;

for each audio sample of one of said input audio signals, said one or more circuits adds said audio sample to one or more right shifted versions of said audio sample; and

said one or more circuits selects a portion of a summed audio signal resulting from said addition.

13. The system according to claim 12, wherein said plurality of inputs comprise one or more analog microphones.

14. The system according to claim 12, wherein said plurality of inputs comprise one or more digital microphones.

15. The system according to claim 12, wherein said one or more circuits are operable to shift each of said one or more right shifted versions of said audio sample by a different number of bits.

16. The system according to claim 12, wherein said one or more circuits are operable to coarsely adjust said levels of said input audio signals in 6 dB steps via said selection of said portion of said summed audio signal.

17. The system according to claim 12, comprising finely adjusting a gain applied to said audio sample, via said adding said audio sample to one or more right shifted versions of said audio sample, to be between a value of 1 and 2.

18. The system according to claim 12, wherein said one or more circuits are operable to select said portion of said summed audio signal based on a type of audio content being processed.

19. The system according to claim 18, wherein said type of audio content is one or more of voice, music, and ringtone.

20. The system according to claim 12, wherein said one or more circuits are operable to select which of said one or more right shifted versions of said audio sample are added to said audio sample via one or more switching elements.

21. The system according to claim 20, wherein said one or more circuits are operable to control said one or more switching elements via a digital control word.

22. The system according to claim 21, wherein said digital control word is dynamically generated.