Stereo Sound Generation Reducing Channel Correlation for Rear Localization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional stereo sound generation systems using two-channel speakers struggle to accurately generate sound images at the rear of a listener due to high correlation between surround channels, leading to front/rear confusion and difficulty in distinguishing rear sound images, as they rely on standard dummy head frequency characteristics that differ from actual users.
Innovation Solution
A stereo sound generation apparatus and method that adjusts output gains and time delays for remaining channel audio signals, using preprocessing filters to reduce correlation between two-channel audio signals and convert them into virtual sound sources at predetermined positions, while correcting signal characteristics and adding signals to create a natural stereo perception.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional stereo sound generation systems use two-channel speakers with standard dummy head frequency characteristics, then the system structure is simple, but the sound image localization at the rear of the listener is inaccurate and front/rear confusion occurs
Solution Approach 1:
The patent segments the audio signal processing into distinct functional blocks: preprocessing filter unit, virtual speaker filter unit, and signal correction filter unit. Each unit performs a specific function (correlation reduction, virtual sound source generation, and signal characteristic correction) to systematically address the localization accuracy problem without overwhelming complexity.
Solution Approach 2:
The preprocessing filter unit performs preliminary action by reducing correlation between surround channels before the signals are processed further. This提前 intervention prevents the front/rear confusion problem from occurring in the first place, improving localization accuracy proactively rather than reactively.
2Measurement precision
If high correlation between left and right surround channels is present, then the system operation is simple, but the ability to generate sound images at the rear of the listener is poor
Solution Approach 1:
The virtual speaker filter unit extracts the essential spatial characteristics needed for rear sound image generation while removing the harmful high correlation between channels. By taking out only the necessary components for accurate localization and leaving behind the correlated signals, the system achieves better rear sound image distinction.
Solution Approach 2:
The signal correction filter unit changes parameters such as output gains and time delays for the processed signals. By adjusting these parameters, the system optimizes the distinction between front and rear sound images while managing the complexity of signal processing.
3Adaptability or versatility
If standard dummy head frequency characteristics are used, then the device complexity is low, but the stereo perception does not match actual user experience
Solution Approach 1:
The patent creates a universally applicable signal processing framework that can adapt to different users' frequency characteristics. The filter units are designed to process signals in a way that can be customized for individual users while maintaining the same basic system structure, achieving adaptability without proportionally increasing complexity.
Data Source
AI summary
A stereo sound generation apparatus and method of reproducing multi-channel sound input signals through two-channel speakers. The stereo sound generation apparatus includes: a preprocessing filter unit to reduce correlation between two-channel audio signals from among multi-channel audio signals and to generate a presence perception, a virtual speaker filter unit to convert the two-channel audio signals output from the preprocessing filter unit into a virtual sound source at a predetermined position, a signal correction filter unit to correct a signal characteristic between remaining multi-channel audio signals excluding the two-channel audio signals, and the two-channel audio signals output from the virtual speaker filter unit, and an addition unit to add signals to be output to a first channel from among the multi-channel audio signals output from the virtual speaker filter unit and the signal correction filter unit, and to add signals to be output to a second channel from among the multi-channel audio signals output from the virtual speaker filter unit and the signal correction filter unit.