3D Sound Reproduction Using HRTF Filters for Elevation Localization
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Solution Overview
Problem
Current 3D sound reproduction technologies fail to effectively localize virtual sound sources to specific elevations, as they are primarily designed for sound generation on a level surface and lack the capability to simulate sound from different elevations accurately.
Innovation Solution
A 3D sound reproducing method and apparatus that utilize head-related transfer filters (HRTFs) to model sound signals from virtual sound sources at predetermined elevations, filtering and amplifying channel signals to simulate the spatial characteristics of sound arrival, allowing for accurate localization of virtual sound sources above or below the level surface of actual speakers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If speakers are arranged only on a level surface for 3D sound reproduction, then the device complexity is reduced and ease of manufacture is improved, but the ability to localize virtual sound sources to predetermined elevations deteriorates
Solution Approach 1:
The patent introduces HRTF filters as an intermediary element between the physical speakers and the listener's ears. These filters process the audio signals to simulate the acoustic effects of sound traveling from elevated positions, allowing virtual sound sources to be localized at predetermined elevations without physically placing speakers at those heights. This resolves the contradiction by maintaining simple speaker arrangement while achieving precise elevation localization through signal processing.
Solution Approach 2:
The patent changes the parameters of the audio signals by applying HRTF filters that modify frequency responses based on simulated elevation angles. By adjusting these acoustic parameters in the digital domain, the system creates the perception of sound coming from elevated positions without changing the physical positions of the speakers, thus maintaining ease of manufacture while achieving localization precision.
2Manufacturing precision
If speakers are installed at desired elevations to achieve accurate 3D sound localization, then the localization precision of virtual sound sources is improved, but the device complexity and ease of manufacture deteriorate
Solution Approach 1:
HRTF filters serve as a computational intermediary that models the complex acoustic paths from elevated virtual sound sources to the listener's ears. Instead of requiring physically complex elevated speaker installations, the filters process signals to recreate the acoustic effects, thereby achieving localization precision without increasing device complexity.
Solution Approach 2:
The patent replaces the mechanical solution of physically installing speakers at elevated positions with a digital signal processing solution using HRTF filters. This substitution eliminates the need for complex mechanical speaker arrangements while achieving the same localization precision through computational acoustic modeling.
3Ease of operation
If conventional 5.1 channel audio is used for sound reproduction, then the ease of operation is maintained, but the ability to provide immersive 3D sound experience deteriorates
Solution Approach 1:
The patent makes the audio system universal by enabling it to handle both conventional 5.1 channel audio and immersive 3D sound reproduction through the same hardware infrastructure. The HRTF filter processing can be applied to standard channel configurations while adding elevation information, allowing the system to adapt between different audio modes without requiring separate operational procedures, thus maintaining ease of operation while improving adaptability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables the effective localization of virtual sound sources to predetermined elevations, providing a realistic 3D audio experience by simulating the complex passage characteristics of sound through the human head and ears, even when speakers are not installed at the desired elevation.
Implementation Method 1
transmitting a sound signal through a head related transfer filter corresponding to a predetermined elevation
Data Source
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AI summary
Provided are a three-dimensional (3D) sound reproducing method and apparatus. The method includes transmitting sound signals through a head related transfer filter (HRTF) corresponding to a first elevation, generating a plurality of sound signals by replicating the filtered sound signals, amplifying or attenuating each of the replicated sound signals based on a gain value corresponding to each of speakers, through which the replicated sound signals will be output, and outputting the amplified or attenuated sound signals through the corresponding speakers.