METHODS AND APPARATUSES FOR ENCODING AND DECODING OBJECT-BASED AUDIO SIGNALS

• US 20160314793A1
• Filed: 07/01/2016
• Published: 10/27/2016
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Dong Soo, Pang, Hee Suk, Lim, Jae Hyun, Yoon, Sung Yong, Lee, Hyun Kook
• Granted Patent: US 9,792,918 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 19/087 using mixed excitation models, e.g. MELP, MBE, split band LPC or HVXC
• CPC Class Codes: G10L 19/20 using sound class specific coding, hybrid encoders or object based coding
• CPC Class Codes: G10L 21/04 Time compression or expansion
• CPC Class Codes: H04S 2400/03 Aspects of down-mixing multi-channel audio to configurations with lower numbers of playback channels, e.g. 7.1 -> 5.1 H04S2400/01 takes precedence
• CPC Class Codes: H04S 2400/11 Positioning of individual sound objects, e.g. moving airplane, within a sound field H04S2420/13 takes precedence
• CPC Class Codes: H04S 2420/01 Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD]
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence

Abstract

Provided are an audio encoding method and apparatus and an audio decoding method and apparatus in which audio signals can be encoded or decoded so that sound images can be localized at any desired position for each object audio signal. The audio decoding method generating a third downmix signal by combining a first downmix signal extracted from a first audio signal and a second downmix signal extracted from a second audio signal; generating third object-based side information by combining first object-based side information extracted from the first audio signal and second object-based side information extracted from the second audio signal; converting the third object-based side information into channel-based side information; and generating a multi-channel audio signal using the third downmix signal and the channel-based side information.

Claims

1. An audio decoding method comprising:

receiving, by an audio decoding apparatus, a downmix signal comprising at least one object signal, and object-based side information generated when the at least one object signal is downmixed into the downmix signal;

receiving, by the audio decoding apparatus, control information for controlling position or level of at least one object signal;

receiving, by the audio decoding apparatus, a HRTF (Head-Related Transfer Function) being a transfer function which describes the transmission of sound waves between a sound source at an arbitrary position and the eardrum;

generating, by the audio decoding apparatus, binaural parameter information using the object-based side information, the control information and the HRTF; and

generating, by the audio decoding apparatus, a binaural signal by processing the downmix signal using the binaural parameter information, wherein the binaural signal is virtual 3D signal.

2. The audio decoding method of claim 1, wherein the downmix signal is modified by performing at least one of level adjustment, sound image processing and effect addition on the downmix signal.

3. The audio decoding method of claim 1, wherein the object-based side information comprises at least one of object level difference information, inter-object cross correlation information, downmix gain information, downmix channel level difference information, and absolute object energy information.

4. The audio decoding method of claim 1, wherein the object-based side information further comprises at least one of envelope information, grouping information, gain information, silent period information, level difference information and residual signal information of object signals.

5. The audio decoding method of claim 4, wherein the envelope information comprises at least one of linear predictive coding (LPC) coefficient information, energy information and power information.

6. The audio decoding method of claim 1, wherein the processed downmix signal is generated using a decorrelated channel signal.

7. An audio decoding apparatus comprising:

a demultiplexer receiving a downmix signal comprising at least one object signal, and object-based side information generated when the at least one object signal is downmixed into the downmix signal;

a parameter converter configured to;

receive control information for controlling position or level of at least one object signal,

receive a HRTF (Head-Related Transfer Function) being a transfer function which describes the transmission of sound waves between a sound source at an arbitrary position and the eardrum,

generate binaural parameter information using the object-based side information, the control information and the HRTF, and,

generate a binaural signal by processing the downmix signal using the binaural parameter information, wherein the binaural signal is virtual 3D signal.

8. The audio decoding apparatus of claim 7, wherein the downmix signal is modified by performing at least one of level adjustment, sound image processing and effect addition on the downmix signal.

9. The audio decoding apparatus of claim 7, wherein the object-based side information comprises at least one of object level difference information, inter-object cross correlation information, downmix gain information, downmix channel level difference information, and absolute object energy information.

10. The audio decoding apparatus of claim 7, wherein the object-based side information further comprises at least one of envelope information, grouping information, gain information, silent period information, level difference information and residual signal information of object signals.

11. The audio decoding apparatus of claim 10, wherein the envelope information comprises at least one of linear predictive coding (LPC) coefficient information, energy information and power information.

12. The audio decoding apparatus of claim 7, wherein the processed downmix signal is generated using a decorrelated channel signal.