In the long history of modern cartography, an enormous number of high quality maps have been deposited in the public domain. While these maps are often older (the map we will consider here is from 1962), the information they contain is vitally important and often can't be found elsewhere. As digital maps are being adopted throughout the humanities, synthesizing the content of old maps into a single coherent (digital) archive is therefore becoming a popular goal for archeologists.
This article details an example of reviving an old map -- in our case, a paper map of Western Theban hills in Upper Egypt. We have adapted this map for Alban-Brice Pimpaud's Archaeological map of Western Thebes, a project of the Supreme Council of Antiquities GIS Center. INSIGHT has also contributed the same 3D map data to the J. Paul Getty Museum's Valley of the Queens project. In both cases, these projects aim to gather as much documentation as possible into a consistent, reliable resource. Below is a rendering of the Theban hills model.
The image below shows a detail of the above rendering, with regularly-spaced curves on the surface at 0.5m intervals.
The curves shown above can be represented as a map (below), when researchers need a 2D view. The polygon mesh itself is separate asset, when a 3D view is required.
Our conversion story begins with Guy Launay, who utilized the 1962 Institut Géographique National (IGN) survey of the Western Theban mountains to create a composite view of the area. Working with A1-sized sheets, he scanned and assembled the paper originals, passing INSIGHT his completed data as a large false-color image. Below is Launay's resulting 2D image, where different colors represent different heights according the inset color key.
INSIGHT converted the 2D color map into a 3D model suitable for typical GIS/cartography use, as seen in the images below. First, our code looks up the height value for each pixel of the source image using Launy's arbitrary color key. Combining the XY location given by the image with the height image, an XYZ point is recovered for each pixel. The result is a traditional height map. We then integrate the XYZ point cloud using the Poisson surface reconstruction method, yielding a polygonal mesh. By lighting and rendering the mesh we obtain the images seen on this page. The model is freely available in Alias Maya format at the links provided here:
Download the Maya file here: [] (~14MB, 7-zip compression)
Download the texture here: [] (~3MB, 7-zip compression)
- Guy digitized the 2M survey as an 8-bit picture: 256 colors = 256 elevation steps, and the XY grid keeps the image correct.
- The IGN data didn't include color, so I referenced a ~2K Google Earth image. See the images below. We 1) used push-pins to mark topo landmarks on a high-res image, 2) grouped the projection texture with the push-pins, and 3) scaled/rotated the group of landmarks into alignment with the mountain model. This is an approximate solution. Even if the solution were perfect, the image quality for the Theban Hills on Google Earth / World Wind / Blue Marble is intended for reference only. The white cliffs oversaturate the satellite sensor, leaving a low-dynamic-range image with lots of illegal values (255, 255, 255).
- The Ramesseum is in a large flat region without data - Several large areas of the landscape are 100% black (i.e., no data)
- In the images below, we extended the landscape with a textured plane to illustrate the above point.
Detail render of the above model.
Plan view of the model, with and without color texture from satellite data (Google Earth).
Current Questions in Authenticity. This day-long symposium at UC Berkeley will be held February 3, 2012, as is open to the public. Several people on the INSIGHT team will be participating. The event is free and open to the public; RSVP to:
INSIGHT's Kevin Cain is serving on the International Scientific Committee for VAST 2011. The International Symposium of Virtual Reality, Archaeology and Culture Heritage (VAST) conference will be held October 18-21, 2011, in Prato, Tuscany, Italy. Kevin previously co-chaired VAST 2004, gave the keynote for VAST 2003 and has presented papers in other years.
Random Control has featured INSIGHT renderings of Chichen Itza here. Thanks to our friends at Random Control for kindly selecting some of our Fryrender images as their second 'Image of the Moment'.