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arXiv · 2507.07347

Rubber band filters: optimal padding without edge artifacts

Zhenyang Xiao·David Burghoff
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Abstract

Bandpass filtering techniques are widely used in spectroscopy. However, conventional symmetric-padding filtering methods introduce boundary artifacts that distort the signal at the edges. We present a rubber band filter: a robust method for achieving band-limited filtering without these detrimental edge artifacts. The technique applies an optimal padding scheme during the filtering process, thereby overcoming longstanding challenges in achieving artifact-free filtering. Importantly, it is iterative and requires only a few extra Fourier transforms over conventional approaches. We demonstrate its superiority and versatility by applying it to three spectroscopic examples -- time-domain spectroscopy, Fourier-transform spectroscopy, and dual-comb spectroscopy.

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Zhenyang Xiao, David Burghoff. 2025-07-10. Rubber band filters: optimal padding without edge artifacts. https://arxiv.org/abs/2507.07347

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