Method and apparatus for embedding spatial information and reproducing embedded signal for an audio signal

• US 8,090,586 B2
• Filed: 05/26/2006
• Issued: 01/03/2012
• Est. Priority Date: 05/26/2005
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Oh, Hyen-O, Pang, Hee Suk, Kim, Dong Soo, Lim, Jae Hyun, Jung, Yang-Won
• Primary Examiner(s): MCFADDEN, SUSAN IRIS
• Application Number:
  US11/915,325
• Publication Number:
  US 20090055196A1
• Time in Patent Office: 2,048 Days
• Field of Search: 704/500
• US Class Current: 704/500
• 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 19/018 Audio watermarking, i.e. embedding inaudible data in the audio signal
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: H04H 20/89 using three or more audio channels, e.g. triphonic or quadraphonic

Abstract

An apparatus encodes or decodes an audio signal using a method by which compatibility with a player of a general mono or stereo audio signal can be provided in coding an audio signal and by which spatial information for a multi-channel audio signal can be stored or transmitted without a presence of an auxiliary data area. The present invention includes extracting side information embedded in non-recognizable component of audio signal components and decoding the audio signal using the extracted side information.

Claims

1. A method of decoding an audio signal, comprising:

receiving, by a hardware apparatus, a downmix signal including embedded spatial information and header information associated with the spatial information, the spatial information comprising spatial parameters to upmix the downmix signal;

detecting, by a hardware apparatus, header information, the header information including a sync word indicating that the spatial information is embedded in the downmix signal, and an insertion bit length indicating a length of bits containing the spatial information;

extracting, by a hardware apparatus, frame data of the spatial information based on the insertion bit length according to an embedded order of spatial information; and

generating, by a hardware apparatus, a multi-channel audio signal by applying the frame data to the downmix signal.

2. The method of claim 1, wherein the downmix signal comprises a plurality of samples units.

3. The method of claim 2, wherein the embedded order indicates that bits for the spatial information in a first sample unit are read from most significant bits to least significant bits, and bits for the spatial information in following samples units are sequentially read from most significant bits to least significant bits.

4. The method of claim 1, wherein a size of header information is determined based on the sync word, and the sync word indicates a start point of the header information.

5. The method of claim 1, further comprising:

extracting, by a hardware apparatus, first error detection code from the header information;

checking, by a hardware apparatus, whether error exists in the header information based on the first error detection code;

extracting, by a hardware apparatus, second error detection code from the frame data; and

checking, by a hardware apparatus, whether error exists in the frame data based on the second error detection code.

6. An apparatus for decoding an audio signal, comprising:

an embedded signal decoding unit configured to;

receive a downmix signal including embedded spatial information and header information associated with the spatial information, the spatial information comprising spatial parameters to upmix the downmix signal and

detect header information, the header information including a sync word indicating that the spatial information is embedded in the downmix signal, and an insertion bit length indicating a length of bits containing the spatial information;

a spatial information decoding unit configured to extract frame data of the spatial information based on the insertion bit length according to an embedded order of spatial information; and

a multi-channel generating unit configured to generate a multi-channel audio signal by applying the frame data to the downmix signal, wherein at least one of the embedded signal decoding unit, spatial information decoding unit, or multi-channel generating unit includes a hardware component.

7. The apparatus of claim 6, wherein the downmix signal comprises a plurality of sample units.

8. The apparatus of claim 7, wherein the embedded order indicates that bits for the spatial information in a first sample unit are read from most significant bits to least significant bits, and bits for the spatial information in following sample units are sequentially read from most bits to least significant bits.

9. The apparatus of claim 6, wherein a size of header information is determined based on the sync word, and the sync word indicates a start point of the header information.

10. The apparatus of claim 6, wherein the embedded signal decoding unit further performs:

extracting first error detection code from the header information;

checking whether error exists in the header information based on the first error detection code;

extracting second error detection code from the frame data; and

checking whether error exists in the frame data based on the second error detection code.

11. A method of encoding an audio signal, comprising:

generating, by a hardware apparatus, a raw pulse-code modulation (PCM) downmix signal by downmixing a multi-channel audio signal;

generating, by a hardware apparatus, spatial information including spatial parameters to upmix the downmix signal;

embedding, by a hardware apparatus, header information of the spatial information in least significant bits of the downmix signal, the header information including a sync word indicating that the spatial information is embedded in the downmix signal and an insertion bit length indicating a length of bits to contain the spatial information; and

embedding, by a hardware apparatus, frame data of the spatial information based on the insertion bit length, according to an embedded order of the spatial information, wherein the embedded order indicates sequentially embedding from most significant bits to the least significant bits.

12. An apparatus for encoding an audio signal, comprising:

an audio signal generating unit configured to generate a raw pulse-code modulation (PCM) downmix signal by downmixing a multi-channel audio signal;

a side information generating unit configured to generate spatial information including spatial parameters to upmix the downmix signal;

a masking threshold computing unit configured to determine an insertion bit length to indicate a length of bits to contain the spatial information based on a masking threshold; and

a bitstream reshaping unit configured to;

embed header information of the spatial information in least significant bits of the downmix signal, the header information including a sync word indicating that the spatial information is embedded in the downmix signal and an insertion bit length indicating a length of bits to contain the spatial information; and

embed frame data of the spatial information based on the insertion bit length, according to an embedded order of the spatial information,

wherein the embedded order indicates sequentially embedding from most significant bits to the least significant bits, and wherein at least one of the audio signal generating unit, the side information generating unit, the masking threshold computing unit, or the bitstream reshaping unit includes a hardware component.