METHOD AND APPARATUS FOR ENCODING AUDIO SIGNAL, AND METHOD AND APPARATUS FOR DECODING AUDIO SIGNAL

• US 20080235033A1
• Filed: 12/21/2007
• Published: 09/25/2008
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: LEE, Nam-suk, Oh, Jae-one, Jeong, Jong-hoon, Lee, Chul-woo, Lee, Geon-hyoung
• Granted Patent: US 8,019,616 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G10L 19/0204 using subband decomposition
• CPC Class Codes: G10L 19/20 using sound class specific coding, hybrid encoders or object based coding

Abstract

Methods and apparatuses for encoding and decoding of an audio signal using a mixture of a time-frequency method and a parametric method according to the audio band are provided. An encoding method of an audio signal includes: dividing input audio signals into a plurality of audio bands; selecting a coding method for each audio band; encoding each audio band according to the selected coding method for each band; and generating a bit stream including all the data encoded for each audio band, wherein selecting a coding method for each band comprises selecting smaller encoded data either from a parametric coding method or a time-frequency coding method.

Claims

1. A method of encoding an audio signal, the method comprising:

dividing an input audio signal into a plurality of audio bands;

selecting a coding method for each of the audio bands;

encoding audio data included in each of the audio bands according to the coding method selected for each of the bands; and

generating a bit stream including all of the encoded audio data included in each of the audio bands,

wherein the selecting the coding method comprises selecting a coding method providing smaller encoded data from among a parametric coding method and a time-frequency coding method.

2. The encoding method of claim 1, wherein the parametric coding method is a Sinusoidal Coding method.

3. The encoding method of claim 1, wherein the time-frequency coding method is an Advanced Audio Coding method.

4. The encoding method of claim 1, wherein the selecting the coding method for each of the audio bands comprises:

calculating a number of sinusoidal signals included in a corresponding audio band among the plurality of audio bands;

selecting the time-frequency coding method if the number of sinusoidal signals is equal to or greater than a predetermined value; and

selecting the parametric coding method if the number of sinusoidal signals is less than the predetermined value.

5. A method of encoding an audio signal, the method comprising:

dividing an input audio signal into a plurality of audio bands;

encoding audio data included in each of the audio bands according to each of a parametric coding method and a time-frequency coding method;

selecting smaller data for each of the audio bands from among the encoded audio data using the parametric coding method and the time-frequency coding method; and

generating a bit stream including all of the encoded audio data selected for each of the audio bands.

6. An apparatus for encoding an audio signal, the apparatus comprising:

a band divider which divides an input audio signal into a plurality of audio bands;

a coding method selector which selects a coding method for each of the audio bands;

an audio encoder which encodes audio data included in each of the audio bands according to the coding method selected for each of the bands; and

a bit stream generator which generates a bit stream including all of the encoded audio data for each of the audio bands,

wherein the coding method selector selects a coding method providing smaller encoded data from among a parametric coding method and a time-frequency coding method.

7. The encoding apparatus of claim 6, wherein the parametric coding method is a Sinusoidal Coding method.

8. The encoding apparatus of claim 6, wherein the time-frequency coding method is an Advanced Audio Coding method.

9. The encoding apparatus of claim 6, wherein the coding method selector selects the time-frequency coding method if the number of sinusoidal signals included in a corresponding audio band among the plurality of audio bands is equal to or greater than a predetermined value, and selects the parametric coding method if the number of sinusoidal signals is less than the predetermined value.

10. A method of decoding an audio signal, the method comprising:

dividing an input bit stream into audio data encoded for a plurality of audio bands;

extracting information on a coding method used by an encoding apparatus for encoding the audio data, for each of the audio bands;

decoding the encoded audio data for each of the audio bands, according to the coding method based on the extracted information; and

generating the audio signal by combining the decoded audio data for the respective audio bands,

wherein the coding method is a coding method providing smaller encoded data that is selected from among a parametric coding method and a time-frequency coding method.

11. The decoding method of claim 10, wherein the parametric coding method is a Sinusoidal Coding method.

12. The decoding method of claim 10, wherein the time-frequency coding method is an Advanced Audio Coding method.

13. The decoding method of claim 10, wherein the time-frequency coding method is selected as the coding method if the number of sinusoidal signals included in the corresponding audio band is equal to or greater than a predetermined value, and the parametric coding method is selected as the coding method if the number of sinusoidal signals is less than the predetermined value.

14. An apparatus for decoding an audio signal, the apparatus comprising:

a bit stream divider which divides an input bit stream into audio data encoded for a plurality of audio bands;

a coding method extractor which extracts information on a coding method used by an encoding apparatus for encoding the audio data, for each of the audio bands;

an audio decoder which decodes the encoded audio data for each of the audio bands, according to the coding method based on the extracted information; and

an audio signal generator which generates the audio signal by combining the decoded audio data for each of the respective audio bands,

wherein the coding method is a coding method providing smaller encoded data that is selected from a parametric coding method and a time-frequency coding method.

15. The decoding apparatus of claim 14, wherein the parametric coding method is a Sinusoidal Coding method.

16. The decoding apparatus of claim 14, wherein the time-frequency coding method is an Advanced Audio Coding method.

17. The decoding apparatus of claim 14, wherein the time-frequency coding method is selected as the coding method if the number of sinusoidal signals included in a corresponding audio band is equal to or greater than a predetermined value, and the parametric coding method is selected if the number of sinusoidal signals is smaller than the predetermined value.

18. A computer readable recording medium having recorded thereon a computer program for executing an audio signal encoding method, the audio signal encoding method comprising:

dividing an input audio signal into a plurality of audio bands;

selecting a coding method for each of the audio bands;

encoding audio data included in each of the audio bands according to the coding method selected for each of the bands; and

generating a bit stream including all the encoded audio data in each audio band,

wherein the selecting the coding method comprises selecting a coding method providing smaller encoded data from among a parametric coding method and a time-frequency coding method.

19. A computer readable recording medium having recorded thereon a computer program for executing an audio signal encoding method, the audio signal encoding method comprising:

dividing an input audio signal into a plurality of audio bands;

encoding audio data included in each of the audio bands by applying each of a parametric coding method and a time-frequency coding method respectively;

selecting smaller data from among the encoded audio data using each of two different coding methods for each of the audio bands; and

generating a bit stream including all of the encoded audio data selected for each of the audio bands.

20. A computer readable recording medium having recorded thereon a computer program for executing an audio signal decoding method, the audio signal decoding method comprising:

dividing an input bit stream into audio data encoded for a plurality of audio bands;

extracting information on a coding method used by an encoding apparatus for encoding the audio data, for each of the audio bands;

decoding the encoded audio data for each of the audio bands, according to the coding method based on the extracted information; and

generating the audio signal by combining the decoded audio data for the respective audio bands,

wherein the coding method is a coding method providing smaller encoded data that is selected from among a parametric coding method and a time-frequency coding method.