Overlay Videos for Quick and Accurate Watermark Identification, Comparison, and Matching

Creating and Using Overlay Videos

Identifying, comparing, and matching watermarks in pre-machine-made papers has occupied scholars of prints and drawings for some time. One popular but arduous approach is to overlay, either manually or digitally, an image of the watermark in question with its presumed match from a known source. For example, a newly discovered watermark in a Rembrandt print might be compared to a similar one reproduced in Erik Hinterding’s Rembrandt as an Etcher (2006). Such an overlay can confirm the pair as identical, i.e., as moldmates, or reveal their differences. But creating an accurate overlay for two images with different scales, orientations, or resolutions using standard image-manipulation tools can be time consuming and, ultimately, unsuccessful.

Part One of this article describes advances in the emerging field of computational art history, specifically the development of digital image processing software, that can be used to semi-automatically create a reliable animated overlay of two watermarks, regardless of their relative “comparability.” Watermarks found in the prints of Rembrandt van Rijn (1606–1669) are used in three case studies to demonstrate the efficacy of user-generated overlay videos.

Part Two discusses how searching for identical watermarks, i.e., moldmates, can be enhanced through the application of a new suite of software programs that exploit the data calculated during the creation of user-generated animated overlays. This novel watermark identification procedure allows for rapid, confident watermark searches with minimal user effort, given the existence of a pre-marked library of watermarks. Using a pre-marked library of Foolscap with Five-Pointed Collar watermarks, four case studies present different categories of previously undocumented matches 1) among Rembrandt’s prints; 2) between prints by Rembrandt and another artist, in this case Jan Gillisz van Vliet (1600/10–1668); and 3) between selected Rembrandt prints and contemporaneous Dutch historical documents.

DOI: 10.5092/jhna.2021.13.2.1

Acknowledgements

The authors wish to express their gratitude to Sound & Vision Publishers for permission for the WIRE Project at Cornell University, of which C. Richard Johnson Jr. is a co-founder, to use their images of the watermarks appearing in Hinterding’s catalogue as a critical part of the watermark identification procedure presented in this article, which we intend to add to the WIRE Project’s website. The authors also thank the Metropolitan Museum of Art, the Morgan Library & Museum, the Staatliche Graphische Sammlung München, the Dutch University Institute for Art History, and Theo and Frans Laurentius for access to images from their radiograph collections. The authors thank Nadine Orenstein (Metropolitan Museum of Art), Erik Hinterding (Rijksmuseum), and Andy Weislogel (Herbert F. Johnson Museum of Art, Cornell University) for their helpful comments on early versions of this article and Daniel Biddle (Stephen Chan Library, New York University) for his assistance.  The authors thank the Getty Foundation Digital Art History Initiative Grant ORG-201943572, “Applying Digital Image Processing Algorithms to the Study of Prints and Drawings” (May 2019–September 2021), which has funded the development and application of computer-based tools that assist in the matching of manufactured patterns in laid paper. Gratitude is extended to the participants in the Foundation for Advancement in Conservation online workshop, “Coding Historical Papers: Identifying Sameness and Difference in Watermarks, Chain Lines, and Laid Lines” on March 1, 3, and 5, 2021 (https://www.iiconservation.org/content/coding-historical-papers-online-workshop), who served as first concept and software testers. Finally, the authors thank Associate Editor Bret Rothstein and Managing Editor Jennifer Henel, who provided invaluable assistance with the editing and layout of this article.

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Review: Peer Review (Double Blind)
DOI: 10.5092/jhna.2021.13.2.1
License:
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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Recommended Citation:
C. Richard Johnson Jr., William A. Sethares, Margaret Holben Ellis, "Overlay Videos for Quick and Accurate Watermark Identification, Comparison, and Matching," Journal of Historians of Netherlandish Art 13:2 (Summer 2021) DOI: 10.5092/jhna.2021.13.2.1