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arXiv · 2405.12899

On a time-frequency blurring operator with applications in data augmentation

Simon Halvdansson
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Abstract

Inspired by the success of recent data augmentation methods for signals which act on time-frequency representations, we introduce an operator which convolves the short-time Fourier transform of a signal with a specified kernel. Analytical properties including boundedness, compactness and positivity are investigated from the perspective of time-frequency analysis. A convolutional neural network and a vision transformer are trained to classify audio signals using spectrograms with different augmentation setups, including the above mentioned time-frequency blurring operator, with results indicating that the operator can significantly improve test performance, especially in the data-starved regime.

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BibTeXRIS

Simon Halvdansson. 2024-05-21. On a time-frequency blurring operator with applications in data augmentation. https://doi.org/10.1007/s00041-025-10164-9

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