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arXiv · 2310.00319

Time-Variant Overlap-Add in Partitions

Hagen Jaeger·Uwe Simmer·Jörg Bitzer·Matthias Blau
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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.

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Hagen Jaeger, Uwe Simmer, Jörg Bitzer, Matthias Blau. 2023-09-30. Time-Variant Overlap-Add in Partitions. https://arxiv.org/abs/2310.00319

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