Time-Variant Overlap-Add in Partitions

TL;DR

This paper presents a partitioned convolution algorithm for real-time, time-variant audio processing in virtual and augmented reality, achieving quick impulse response switching with minimal artifacts and efficient resource usage.

Contribution

It introduces a novel partitioned convolution method that enables artifact-free, real-time switching of impulse responses with constant computational load and low memory requirements.

Findings

Achieves perceptually seamless switching between impulse responses.

Maintains constant computational load during processing.

Low memory footprint suitable for real-time applications.

Abstract

Virtual and augmented realities are increasingly popular tools in many domains such as architecture, production, training and education, (psycho)therapy, gaming, and others. For a convincing rendering of sound in virtual and augmented environments, audio signals must be convolved in real-time with impulse responses that change from one moment in time to another. Key requirements for the implementation of such time-variant real-time convolution algorithms are short latencies, moderate computational cost and memory footprint, and no perceptible switching artifacts. In this engineering report, we introduce a partitioned convolution algorithm that is able to quickly switch between impulse responses without introducing perceptible artifacts, while maintaining a constant computational load and low memory usage. Implementations in several popular programming languages are freely available via GitHub.