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arXiv · 2303.12098

Reading hidden writing and drawings on papyrus using speckle optical technique and multispectral images

L. Buffarini·H. J. Rabal·N. L. Cap·E. E. Grumel·M. Trivi·M. Tebaldi
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Abstract

We carried out an experimental set-up for reading a hidden drawing under papyrus using an optical technique based on the speckle phenomenon that is observed when a rough surface is illuminated by laser light. We propose the use of several wavelengths of light illumination and adaptive algorithms to process the speckle images. We employ a set of filters to produce better discrimination of the results as visually judged. This approach is a cheap and relatively simple non-destructive and non-invasive procedure that could be extended to other painted objects or subsurface hidings of archaeological interest, as well as, to other dynamic speckle experiments.

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L. Buffarini, H. J. Rabal, N. L. Cap, E. E. Grumel, M. Trivi, M. Tebaldi. 2023-03-21. Reading hidden writing and drawings on papyrus using speckle optical technique and multispectral images. https://arxiv.org/abs/2303.12098

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