3D Audio Renderer Spatial Extent Simulation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current binaural and multi-channel spatialization processing techniques for 3D audio rendering are costly and inefficient, particularly when simulating spatially extended sound sources, as they incur significant computational costs and generate audible artifacts like timbre coloration and phase distortion.

Innovation Solution

A method that simulates spatially extended sound sources by panning input signals over multiple output channels, using a bank of decorrelation filters and energy scaling factors, allowing for efficient computation comparable to processing a point source, and implements integer delay values to avoid spectral inaccuracies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If pseudo-stereo techniques are used to simulate spatially extended sources, then spatial width is increased, but audible artifacts including timbre coloration and phase distortion are generated

Engineering Contradiction:

Improvespatial widthVSAvoidaudible artifacts

Core Design Contradiction:

Volume of moving objectVSObject-generated harmful factors

Solution Approach 1:

The patent creates multiple copies of the input signal through different processing paths (direct path, early reflection path, late reflection path) to simulate spatially extended sources. Each path is processed independently and then combined to create the final output, avoiding the need for traditional pseudo-stereo techniques that generate audible artifacts.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent segments the spatialization process into distinct components: direct sound, early reflections, and late reflections. Each segment is processed separately with appropriate decorrelation and spatial positioning, then combined to create a realistic spatially extended source without the artifacts of conventional approaches.

Inventive Principle:

Principle #1Segmentation

2Reliability

If pseudo-stereo algorithms are applied to each monophonic source individually, then spatial decorrelation is achieved, but substantial per-source computational costs are incurred

Engineering Contradiction:

Improvespatial decorrelationVSAvoidprocessing efficiency

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent merges multiple signal paths (direct, early reflections, late reflections) into a unified processing framework. Instead of processing each source independently through separate pseudo-stereo algorithms, the system combines multiple processed versions of the same input signal, significantly reducing computational overhead while maintaining spatial decorrelation.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent creates a universal processing framework that handles both point sources and spatially extended sources using the same architectural structure. The multi-channel decorrelation filter bank serves multiple functions: it provides spatialization, decorrelation, and spatial extent simulation simultaneously, eliminating the need for separate processing chains.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If first-order linear interpolation is used for fractional delay implementation, then continuous ITD variation is achieved, but significant spectral inaccuracies occur at high frequencies

Engineering Contradiction:

Improvecontinuous ITD variationVSAvoidspectral accuracy

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent implements dynamic spatialization where the interaural time delay (ITD) varies continuously with source position. By using multiple decorrelated signal paths with different delay characteristics, the system achieves continuous ITD variation without relying on first-order linear interpolation, thereby maintaining spectral accuracy across all frequencies.

Inventive Principle:

Principle #15Dynamics

4Volume of moving object

If multiple decorrelated signals are generated for spatially extended sources, then spatial extent simulation is improved, but substantial per-source computation costs are incurred

Engineering Contradiction:

Improvespatial extentVSAvoidprocessing efficiency

Core Design Contradiction:

Volume of moving objectVSProductivity

Solution Approach 1:

The patent replaces the computationally intensive approach of generating multiple independent decorrelated signals with a more efficient method using a bank of decorrelation filters applied to a multi-channel signal. This substitution maintains the spatial extent simulation quality while dramatically reducing the computational burden by reusing the same input signal across multiple filtered paths.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS8488796B23D audio renderer

Publication Date: 2013.07.16 CREATIVE TECHNOLOGY LTD

AI summary

A method for simulating spatially extended sound sources comprising: panning a first input signal over a plurality of output channels to generate a first multi-channel directionally encoded signal; panning a second input signal over the plurality of output channels to generate a second multi-channel directionally encoded signal; combining the first and second multi-channel directionally encoded signals to generate a plurality of loudspeaker output channels; and applying a bank of decorrelation filters on the loudspeaker output channels.