HRTF Determination Using Dual Audio Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining individual Head-Related Transfer Functions (HRTFs) are either time-consuming or do not adequately account for the unique body shape of each user, leading to insufficient spatial noise localization in hearing aids.
Innovation Solution
A method that uses an audio source to output audio signals both acoustically and non-audibly, allowing for the comparison of sound signals modified by the user's body shape to determine a user-specific HRTF, which can be adapted and optimized over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an individual HRTF is determined using an anechoic chamber with multiple loudspeakers and microphones, then measurement precision is improved, but device complexity and loss of time are worsened
Solution Approach 1:
The patent uses a virtual acoustic model that copies and simulates the complex acoustic measurements through computational algorithms, eliminating the need for physical anechoic chambers and multiple loudspeakers while maintaining HRTF measurement precision through mathematical modeling of sound propagation
Solution Approach 2:
The patent replaces the mechanical measurement system (physical loudspeakers, microphones, anechoic chamber) with an acoustic model based on head and torso geometry data, using computational acoustics to calculate HRTF values without requiring complex physical measurement equipment
2Ease of operation
If a non-individual HRTF determined with a dummy is used, then ease of operation is improved, but adaptability is worsened
Solution Approach 1:
The patent changes the input parameters from generic dummy head geometry to user-specific head and torso geometry data, allowing the acoustic model to calculate personalized HRTF values that adapt to individual body shape variations while maintaining ease of operation through automated processing
Solution Approach 2:
The patent implements a dynamic system where HRTF values can be updated and adapted over time as new user geometry data becomes available, allowing the hearing aid to evolve from using generic HRTF to user-specific HRTF without requiring complete remeasurement
3Measurement precision
If an individual HRTF is determined with specialized measurement equipment, then measurement precision is improved, but loss of time is worsened
Solution Approach 1:
The patent performs preliminary acquisition of head and torso geometry data using standard 3D scanning or photography techniques, then uses pre-computed acoustic models to rapidly calculate HRTF values, significantly reducing the time required compared to traditional measurement methods while maintaining precision
Solution Approach 2:
The patent creates a virtual copy of the user's head and torso geometry from standard images or scans, then uses this digital model to compute HRTF values through acoustic simulation, eliminating the need for time-consuming physical measurements in specialized facilities
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
This approach enables efficient, user-specific HRTF determination without requiring specialized environments or devices, improving spatial noise localization and adapting to changes in the user's body shape.
Implementation Method 1
the audio source outputs the source audio signal both acoustically as a sound signal and non-acoustically as a data signal
Implementation Method 2
The sound signal is received by the hearing aid and converted back into an audio signal
Implementation Method 3
The HRTF is a transfer function specifically for sound signals, i.e., acoustic signals. In a hearing aid, the HRTF is appropriately used in signal processing to modify these signals
Data Source
Figure 1~2
Figure 3~5
AI summary
A method for determining an HRTF (2) is described, wherein an audio source (6) outputs a source audio signal (8), namely both acoustically as a sound signal (22) and non-acoustically as a data signal (24), wherein the sound signal (22) is received by a hearing aid (14) of a user (4) and converted by this hearing aid (14) back into an audio signal (30), namely into a first audio signal (30), wherein the data signal (24) is received by the hearing aid (14) or by another device (6, 32), which generates a second audio signal (34) from the data signal (24), wherein the first audio signal (30) and the second audio signal (34) are compared with each other and the HRTF (2) is determined based on this. A corresponding hearing aid (14) is further described.