The noninvasive digital restoration of ancient texts written in carbon black ink and hidden inside artifacts has proven elusive, even with advanced imaging techniques like x-ray-based micro-computed tomography (micro-CT). This paper identifies a crucial mistaken assumption: that micro-CT data fails to capture any information representing the presence of carbon ink. Instead, we show new experiments indicating a subtle but detectable signature from carbon ink in micro-CT. We demonstrate a new computational approach that captures, enhances, and makes visible the characteristic signature created by carbon ink in micro-CT. This previously "unseen" evidence of carbon inks, which can now successfully be made visible, is a discovery that can lead directly to the noninvasive digital recovery of the lost texts of Herculaneum.

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Notes/Citation Information

Published in PLOS One, v. 14, no. 5, p. 1-17.

© 2019 Parker et al.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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Funding Information

W.B.S. acknowledges funding from the National Science Foundation (award IIS-1422039), Google, Lee and Stacie Marksbury, and John and Karen Maxwell.

Access to SEM/EDS characterization instruments and staff assistance was provided by the Electron Microscopy Center at the University of Kentucky, supported in part by the National Science Foundation/EPSCoR Award No. 1355438 and by the Commonwealth of Kentucky.

Related Content

S1 Appendix: Detailed descriptions of materials, methods, and computational processes. Includes report on alternative ink detection filters developed prior to the work presented here. https://doi.org/10.1371/journal.pone.0215775.s001

The appendix is also available as the additional file listed at the end of this record.

journal.pone.0215775.s001.pdf (8032 kB)
Expanded materials and methods