Multi-channel conversion method based on spherical harmonic expansion

A conversion method and multi-channel technology, applied in the field of acoustics, can solve the problem of inaccurate sound field restoration in the listening area

Inactive Publication Date: 2014-06-25
BEIJING UNIV OF TECH
View PDF4 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Aiming at the inaccurate restoration of the sound field in the listening area of ​​the existing multi-channel audio system simplification method, the present invention proposes a multi-channel con

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Multi-channel conversion method based on spherical harmonic expansion
  • Multi-channel conversion method based on spherical harmonic expansion
  • Multi-channel conversion method based on spherical harmonic expansion

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0064] An embodiment employs the following sub-steps:

[0065] Step 3.1 Establish a multi-channel conversion model in the frequency domain, and substitute this model into the converted system sound pressure In the spherical harmonic expansion of . The multi-channel conversion model in the frequency domain can be expressed as:

[0066] q(ω)=Ws(ω)

[0067] in s ( ω ) = s 1 ( ω ) · · · ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a multi-channel conversion method based on spherical harmonic expansion. The multi-channel conversion method is mainly used for converting an L1-path multi-channel loudspeaker system into an L2-path multi-channel loudspeaker system. Based on the linear superposition theory of a sound field, spherical harmonics with corresponding orders are adopted according to different numbers of channels for calculating the sound field of the loudspeaker system which is not converted and the sound field of the loudspeaker system which is obtained after conversation, and gain coefficients of each loudspeaker of the loudspeaker system obtained after conversation are calculated under the situation that the spherical harmonic expansion sound field of the loudspeaker system which is not converted and the spherical harmonic expansion sound field of the loudspeaker system which is obtained after conversation are the same under the certain order. According to the multi-channel conversion method based on spherical harmonic expansion, the real-time algorithm complexity is low, the sound field of an original reproducing system in a listening area can be recovered on the system obtained after conversation, the method can be used for streamline compression and hybrid technology of a multi-channel three-dimensional audio system, effective compatibility of various loudspeaker reproduction systems can be achieved, and the transmission bandwidth is reduced.

Description

technical field [0001] The invention belongs to the field of acoustics, and in particular relates to the simplified compression and up-mixing technology of a multi-channel three-dimensional audio system. Background technique [0002] 5.1 surround sound has been widely used in various traditional cinemas and home theaters, but the 5.1 channel lacks the interpretation of height and distance information, which cannot make the audience feel immersive. Many advanced scientific research institutions are conducting research on multi-channel audio systems. Among them, the Japan Broadcasting Corporation (NHK) Science and Technology Laboratory developed a 22.2-channel prototype system in 2004 and listed it as the next-generation ultra-high-definition system. Three-dimensional audio standard for televisions. The MPEG (Moving Pictures Experts Group) standard working group is also working on the development of the three-dimensional audio standard MPEG-H based on NHK22.2 channels. The p...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): H04S3/00
Inventor 鲍长春步兵贾懋珅周岭松孙正阳朱蓉
Owner BEIJING UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products