Historical parchment scrolls are fragile, and consequently, many such scrolls cannot be unrolled, so that their contents have remained hidden for centuries. I will describe several stages in the development of our method to perform a 'virtual unrolling' of such documents from their X-ray tomographic scans. A critical element is the segmentation of the images in order to separate the parchment from the background, which is complicated by both holes in the parchment and the fusing of adjacent rolled layers. Since this causes standard segmentation algorithms to produce errors, we have devised several new algorithms to cope with such data. Once segmentation is achieved, the parchment is virtually flattened, and the ink density recovered to produce a reconstruction of the parchment surface. Examples of our results are shown on several historic scrolls.
Paul Rosin is Professor at the School of Computer Science & Informatics, Cardiff University. Previous posts include lecturer at the Department of Information Systems and Computing, Brunel University London, UK, a research scientist at the Institute for Remote Sensing Applications, Joint Research Centre, Ispra, Italy, and lecturer at the Curtin University of Technology, Perth, Australia.