Head-Related Transfer Function Generator Using Pinna Shape Data

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional head-related transfer function selecting devices can only select from pre-stored functions and require accurate measurement in anechoic chambers, which are limited and difficult for general users to access, especially those without acoustic knowledge.

Innovation Solution

A head-related transfer function generator that acquires and models head-related impulse responses using a window function, Fourier transforms, and discriminant analysis to derive frequency bands and relative amplitudes, allowing for the generation of a modeled head-related transfer function without direct measurement, and integrates pinna shape data to identify relevant frequency bands.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If head-related transfer function is measured in an anechoic chamber, then measurement precision is improved, but device complexity and accessibility are worsened

Engineering Contradiction:
Improvehead-related transfer function measurement precisionVSAvoidmeasurement environment complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent creates a virtual model (copy) of the head-related transfer function based on pinna shape data, replacing the need for physical measurement in complex anechoic chambers. The system generates a modeled head-related transfer function that replicates the acoustic characteristics without requiring specialized measurement environments.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent replaces the mechanical/acoustic measurement system (requiring anechoic chambers and specialized equipment) with a computational system that uses machine learning models and algorithms to generate head-related transfer functions from pinna shape data.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If head-related transfer function is measured in ordinary environments, then ease of operation is improved, but measurement precision is worsened

Engineering Contradiction:
Improvemeasurement accessibilityVSAvoidhead-related transfer function measurement precision
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The system creates a computational copy of the acoustic measurement process, allowing measurements to be performed in ordinary environments while maintaining precision through algorithmic processing and machine learning models that compensate for environmental variations.

Inventive Principle:
Principle #26Copying

3Productivity

If database of head-related transfer functions is used, then productivity is improved, but adaptability is worsened

Engineering Contradiction:
Improvehead-related transfer function selection speedVSAvoidlistener-specific customization capability
Core Design Contradiction:
ProductivityVSAdaptability or versatility

Solution Approach 1:

The system performs preliminary processing of pinna shape data and pre-trains machine learning models with diverse head-related transfer function data, enabling rapid generation of customized results without requiring full measurements or database searches for each listener.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system changes the input parameters from requiring actual acoustic measurements to using only pinna shape geometric data, allowing the same input data to serve multiple purposes and enabling both rapid processing and high adaptability through the flexible machine learning framework.

Inventive Principle:
Principle #35Parameter changes

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 reproduction of head-related transfer functions for listeners without actual measurement, improving accessibility and accuracy in three-dimensional acoustic systems and virtual reality applications.

Implementation Method 1

an early head-related transfer function generating unit configured to calculate an initial head-related impulse response by applying a window function to the actually measured head-related impulse response and generate data representing an early head-related transfer function by performing a Fourier transform on the initial head-related impulse response

Methodology Applied
Scientific EffectFourier transform:

Data Source

PatentUS11337021B2Head-related transfer function generator, head-related transfer function generation program, and head-related transfer function generation method
Publication Date: 2022.05.17 CHIBA INSTITUTE OF TECHNOLOGY
  • US11337021B2 patent drawing
  • US11337021B2 patent drawing
  • US11337021B2 patent drawing

AI summary

An object is to acquire a head-related transfer function reproducing features of a head-related transfer function of a listener without actually measuring the head-related transfer function of the listener. A head-related transfer function generator includes: acquiring data that represents an actually measured head-related impulse response of sound waves arriving at external auditory meatus entrances of a listener for training; calculating an initial head-related impulse response by applying a window function to the actually measured head-related impulse response and generating data representing an early head-related transfer function by performing a Fourier transform on the initial head-related impulse response; dividing the early head-related transfer function into a plurality of frequency bands; and executing a process of extracting a peak or a notch on the basis of curvature of the early head-related transfer function and a process of determining a relative amplitude for each of the plurality of frequency bands and generating data representing a modeled head-related transfer function of the listener for training by interpolating points representing the relative amplitudes.