Audio Localization via Spatial Filtering to Reduce Aliasing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio processing technologies face challenges in accurately localizing an audio image due to spatial aliasing, which requires additional speaker arrays to enhance the upper limit temporal frequency, increasing costs.
Innovation Solution
An audio processing apparatus and method that includes an orientation information acquisition unit and a spatial filter application unit, which applies a spatial filter with characteristics defined by the orientation information to the sound pickup signal from a microphone array, reducing spatial aliasing by preferentially transmitting specific frequency bands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If additional speaker arrays are used to enhance the upper limit temporal frequency, then sound quality and audio image localization are improved, but device complexity and cost increase
Solution Approach 1:
The patent extracts and removes the spatial aliasing component from the sound field reproduction system. By identifying the upper limit spatial frequency caused by discrete speaker arrangement and eliminating its harmful effects through signal processing, the system achieves accurate audio image localization without requiring additional speaker arrays, thus resolving the contradiction between localization accuracy and device complexity
Solution Approach 2:
The patent changes the parameter of upper limit temporal frequency by processing the speaker drive signal to remove spatial aliasing components. Through frequency domain analysis and selective filtering based on the relationship between spatial frequency and temporal frequency, the system enhances the effective upper limit temporal frequency beyond what would be possible with the physical speaker arrangement alone, improving sound quality without adding hardware
2Device complexity
If discrete speaker arrangement is used, then device complexity is reduced, but spatial aliasing occurs and degrades sound quality
Solution Approach 1:
The patent converts the harmful spatial aliasing effect into a beneficial filtering opportunity. By deliberately identifying the spatial aliasing frequency components based on the known speaker arrangement, the system can selectively remove only these specific frequency components from the speaker drive signal, thereby eliminating the harmful effects while preserving the simplicity of the discrete speaker configuration and maintaining sound quality
3Manufacturing precision
If higher upper limit temporal frequency is achieved, then sound quality improves, but spatial aliasing increases with discrete arrangement
Solution Approach 1:
The patent applies preliminary anti-action by preemptively removing spatial aliasing components from the speaker drive signal before they can degrade the sound quality. Through frequency domain analysis and selective filtering based on the relationship between spatial and temporal frequencies, the system prevents spatial aliasing from affecting the reproduced sound, thereby enabling high upper limit temporal frequency achievement without the harmful effects of spatial aliasing
Data Source
AI summary
The present technology relates to an audio processing apparatus and method capable of improving localization of an audio image at lower cost, and a program.A microphone array picks up a planar wave of the audio from a sound source. A drive signal generation unit generates a speaker drive signal of a spatial domain on the basis of a spatial frequency spectrum of a sound pickup signal acquired by the sound pickup by the microphone array. An orientation information acquisition unit acquires talker's orientation information on an orientation of a talker. A spatial filter application unit performs a filter processing on the speaker drive signal by use of a spatial filter defined by the talker's orientation information thereby to reduce spatial aliasing. The present technology can be applied to a spatial aliasing controller.