THE GREAT PARCHMENT BOOK WEBSITE HAS GONE LIVE!

The Great Parchment Book website has gone live!

You can now start to explore the Great Parchment Book for yourself.

A good place to start is the video on the Home Page which illustrates the challenging nature of the project.

To continue your exploration, click on “Take a look inside the book” or search for a person, place or livery company.

If you want to know more about the historical background, book or project history, investigate the history tabs at the top of the Home Page.

The website is dynamic. Work is continuing on the transcription, and transcriptions and images will continue to be added to the site. Once the transcription is complete, the book history page will be expanded to take account of new insights into the codicology of the book, and to explain the arrangement of the folios.

The Great Parchment Book Blog is now embedded into the website and you can subscribe to the Blog on the website. Work is continuing to align the original Blog and the website Blog.

If you have any comments on the website, or can offer additional insights into the Great Parchment Book and what it reveals about the people, places and organisations involved in the history of 17th century Ulster, please share via the Blog or use the comment form at the bottom of the website Home Page.

Exploring and Flattening Parchments Interactively

We recently had our paper, Interactive Exploration and Flattening of Deformed Historical Documents, accepted for publication in the Computer Graphics Forum and to be presented at Eurographics 2013.

Our procedure begins by capturing a set of high resolution photographs of the pages of the book, and generating from them a detailed 3D scan of each page. Typically we need between 40 and 60 images per folio to capture every fold and crease in sufficient detail. Using these scans we attempt to “virtually restore” the pages and produce undistorted images of the pages.

Three pages of the Great Parchment Book. Top: our reconstructed surface model. Bottom: the models textured with images of the text. The surface models show the level of distortion the parchment has suffered, which differs greatly from folio to folio.

Having generated scans for the majority of the pages in the book, we realized that producing a globally flattened and undistorted image of a page is not always possible for the more damaged pages due to the sheer variety and complexity of the deformations present.

To get around this problem we instead created an interactive browser application, effectively a “Google Earth for documents”. Google Earth allows users to navigate over the surface of the earth following lines of latitude and longitude, and always see a locally flat map of the region of the earth they are looking at. In a similar way, our viewer allows users to navigate over the surface of the page following lines of text, and see a locally undistorted image of the region of the page currently in view. One of the key insights here is that flattening multiple small, local regions of a page is much simpler than flattening the entire page at once.

Regions of text before and after the local flattening procedure

We also understand the importance in the digital cultural heritage field of being able to trust digital representations of artifacts. To help users gauge the quality of the reconstruction and be more confident in what they read, our application includes a “provenance feature” which allows them to compare the 3D scan and the original photographs which were used to generate the scan. For every point on the scan surface, the application can display an original input photograph next to it which allows the user to verify what they are seeing in the scan.

Left: A region of a reconstruction of a page, containing a suspect marking which looks like it might have been introduced by an error in the reconstruction process. Right: One of the original photographs, looking at the same region of the page. We can see that the marking is in fact present on the page.

Our application will soon be used as an additional tool for the transcription of the Great Parchment Book and possibly later as a means of dissemination of the book’s content.

Virtual flattening

Alongside all the conventional conservation work happening on the book, here at UCL we are experimenting with ways to “virtually restore” the book using a mix of imaging, computer vision, and computer graphics techniques.

Our approach is two-fold. First create a virtual 3D model of each page, and second flatten the 3D model into a 2D plane. It sounds fairly simple but is deceptively complex.

Creating detailed models of the pages requires a careful imaging process to try to get inside every crease and fold and capture every letter at as high a resolution as possible. The result is a set of 50 or so high-resolution images (for each page of the book). These are fed into a pipeline of computer programmes which (after a considerable amount of processing time) generates the 3D model.

Before virtual flattening

3D mesh

Then comes the problem of flattening the page in a sensible way. At first glance, it would seem that we want to just “unfold” the page as you would a crumpled piece of paper. However, the way the pages are distorted is not like crumpling a piece of paper and so there is no nice and easy way to “unfold” them. So now the problem becomes “how can we flatten the page into a 2D plane in such a way that the text does not become distorted”, and that is what we are trying to solve at the moment.

After virtual flattening