Audio signal coding method and apparatus

• US 9,779,749 B2
• Filed: 11/02/2016
• Issued: 10/03/2017
• Est. Priority Date: 10/08/2011
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Miao, Lei, Liu, Zexin
• Primary Examiner(s): PULLIAS, JESSE SCOTT
• Application Number:
  US15/341,451
• Publication Number:
  US 20170053661A1
• Time in Patent Office: 335 Days
• Field of Search: 704200-232, 704500-504
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: G10L 19/087 using mixed excitation models, e.g. MELP, MBE, split band LPC or HVXC
• CPC Class Codes: G10L 19/18 Vocoders using multiple modes
• CPC Class Codes: G10L 19/265 Pre-filtering, e.g. high frequency emphasis prior to encoding
• CPC Class Codes: G10L 21/038 using band spreading techniques
• CPC Class Codes: G10L 25/18 the extracted parameters being spectral information of each sub-band

Abstract

The present disclosure relates to an audio signal coding method and apparatus. The method includes categorizing audio signals into high-frequency audio signals and low-frequency audio signals, coding the low-frequency audio signals using a corresponding low-frequency coding manner according to characteristics of low-frequency audio signals, and selecting a bandwidth extension mode to code the high-frequency audio signals according to the low-frequency coding manner and/or characteristics of the audio signals.

Claims

1. An audio signal coding method, comprising:

categorizing audio signals into high-frequency audio signals and low-frequency audio signals;

coding the low-frequency audio signals using at least one of a time domain (TD) coding manner or a frequency domain (FD) coding manner; and

selecting a bandwidth extension mode to code the high-frequency audio signals according to at least one of a low-frequency coding manner by;

selecting a time domain bandwidth extension (TD-BWE) mode to perform TD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the TD coding manner; and

selecting a frequency domain bandwidth extension (FD-BWE) mode to perform FD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the FD coding manner.

2. The audio signal coding method according to claim 1, further comprising performing delay processing on the high-frequency audio signals or the low-frequency audio signals such that delay of the high-frequency audio signals and delay of the low-frequency audio signals are the same at a decoding end.

3. The audio signal coding method according to claim 1, wherein the coding the high-frequency audio signals comprises coding the high-frequency audio signals after performing first delay for the high-frequency audio signals such that coding delay and decoding delay of the audio signals are a sum of the first delay and second delay, wherein the first delay is delay generated during coding and decoding of the low-frequency audio signals, and wherein the second delay is delay generated during coding of the high-frequency audio signals.

4. The audio signal coding method according to claim 1, wherein the low-frequency audio signals are delayed by a difference between the second delay and the first delay after being coded when the first delay is smaller than or equal to than the second delay such that coding delay and decoding delay of the audio signals are the second delay, wherein the high-frequency audio signals are delayed by a difference between the first delay and the second delay after being coded when the first delay is larger than the second delay such that coding delay and decoding delay of the audio signals are the first delay, wherein the first delay is delay generated during coding and decoding of the low-frequency audio signals, and wherein the second delay is delay generated during coding of the high-frequency audio signals.

5. The audio signal coding method according to claim 1, wherein coding the high-frequency audio signals comprises coding the high-frequency audio signals after performing third delay for the high-frequency audio signals, wherein the low-frequency audio signals are delayed by a difference between a sum of the second delay and the third delay and the first delay after being coded when the first delay is smaller than or equal to the second delay such that coding delay and decoding delay of the audio signals are the sum of the second delay and the third delay, wherein the high-frequency audio signals are delayed by a difference between the first delay and a sum of the second delay and the third delay after being coded when the first delay is larger than the second delay, or the low-frequency audio signals are delayed by a difference between a sum of the second delay and the third delay and the first delay when the first delay is larger than the second delay such that coding delay and decoding delay of the audio signals are the first delay or the sum of the second delay and the third delay.

6. An audio signal coding apparatus, comprising:

a processor configured to;

categorize audio signals into high-frequency audio signals and low-frequency audio signals;

code the low-frequency audio signals using at least one of a time domain (TD) coding manner or a frequency domain (FD) coding manner; and

select a bandwidth extension mode to code the high-frequency audio signals according to a low-frequency coding manner by;

selecting a time domain bandwidth extension (TD-BWE) mode to perform TD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the TD coding manner; and

selecting a frequency domain bandwidth extension (FD-BWE) mode to perform FD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the FD coding manner.

7. The audio signal coding apparatus according to claim 6, wherein the processor is further configured to:

decode the low-frequency audio signals, wherein first delay is generated during the coding and decoding of the low-frequency audio signals;

code the delayed high-frequency audio signals after delaying the high-frequency audio signals by the first delay such that coding delay and decoding delay of the audio signals are a sum of the first delay and second delay, wherein the second delay is generated during the coding of the high-frequency audio signals.

8. The audio signal coding apparatus according to claim 6, wherein the processor is further configured to:

delay the coded low-frequency audio signals by a difference between the second delay and the first delay when the first delay is smaller than or equal to the second delay after coding the low-frequency audio signals such that coding delay and decoding delay of the audio signals are the second delay; and

delay the coded high-frequency signals by a difference between the first delay and the second delay when the first delay is larger than the second delay after coding the high-frequency audio signals such that coding delay and decoding delay of the audio signals are the first delay, wherein the first delay is delay generated during coding and decoding of the low-frequency audio signals, and wherein the second delay is delay generated during coding of the high-frequency audio signals.

9. The audio signal coding apparatus according to claim 6, wherein the processor is further configured to:

code the high-frequency audio signals after performing third delay for the high-frequency audio signals; and

delay the coded low-frequency audio signals by a difference between a sum of the second delay and the third delay and the first delay when the first delay is smaller than or equal to the second delay after coding the low-frequency audio signals such that coding delay and decoding delay of the audio signals are the sum of the second delay and the third delay;

delay the coded high-frequency audio signals by a difference between the first delay and a sum of the second delay and the third delay when the first delay is larger than the second delay after coding the high-frequency audio signals;

or

delay the coded low-frequency audio signals by a difference between a sum of the second delay and the third delay and the first delay when the first delay is larger than the second delay after coding the low-frequency audio signals such that coding delay and decoding delay of the audio signals are the first delay or the sum of the second delay and the third delay, wherein the first delay is delay generated during coding and decoding of the low-frequency audio signals, and wherein the second delay is delay generated during coding of the high-frequency audio signals.

10. An audio signal coding method, comprising:

categorizing audio signals into high-frequency audio signals and low-frequency audio signals;

coding the low-frequency audio signals using at least one of a time domain (TD) coding manner or a frequency domain (FD) coding manner;

selecting a time domain bandwidth extension (TD-BWE) mode to perform TD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the TD coding manner and the audio signals are voice signals; and

selecting a frequency domain bandwidth extension (FD-BWE) mode to perform FD coding for the high-frequency audio signals when at least one of the low-frequency audio signals do not need to be coded using the TD coding manner or the audio signals are not voice signals.

11. An audio signal coding apparatus, comprising:

a memory comprising instructions; and

a processor coupled to the memory and that, when the instructions are executed, is configured to;

categorize audio signals into high-frequency audio signals and low-frequency audio signals;

code the low-frequency audio signals using at least one of a time domain (TD) coding manner or a frequency domain (FD) coding manner select a time domain bandwidth extension (TD-BWE) mode to perform TD coding for the high-frequency audio signals when the low-frequency audio signals should be coded using the TD coding manner and the audio signals are voice signals; and

select a frequency domain bandwidth extension (FD-BWE) mode to perform FD coding for the high-frequency audio signals when the low-frequency audio signals do not need to be coded using the TD coding manner or the audio signals are not voice signals.