Polynomial Texture Mapping

Polynomial Texture Mapping (PTM) is a technique that enables the production of detailed surface models of particular artefacts from a series of digital photographs (Malzbender et al 2001; Mudge et al 2005). This technique is achieved by taking multiple photographs of an object from a fixed location, with a controlled light source moved between each exposure, or by deriving the light source's location and orientation from highlights appearing on a reference object. The resulting series of images is used to produce a single PTM file via the HP Labs PTM fitter software. The PTM viewer enables a virtual light source to be moved across the virtual scene. The viewer can also vary lighting intensity, add additional virtual lights, derive surface models and to carry out image processing tasks such as edge detection.

The ACRG PTM capture rig enables very fast acquisition of PTM data, with variable sample sizes. It has being developed through a collaborative venture involving Archaeology and Electronics and Computer Science at the University of Southampton. Our rig design builds on published designs - Malzbender et al 2001, Hawkins et al 2001 and Mudge et al 2005.

Hawkins T., Cohen J., Debevec P. (2001) A photometric approach to digitizing cultural artifacts. In Arnold, D., Chalmers, A., Fellner, D. (eds) Proceedings 2nd International Symposium on Virtual Reality, Archaeology, and Cultural Heritage, Glyfada, Greece, November 2001: 333 - 342  

Malzbender, T., Gelb, D., Wolters, H.: Polynomial texture maps. In SIGGRAPH ’01: Proceedings of the 28th annual conference on Computer graphics and interactive techniques (New York, NY, USA, 2001), ACM Press, pp. 519–528.

Mudge M., Voutaz J.P., Schroer C. and Lum M. (2005) Reflection Transformation Imaging and Virtual Representations of Coins from the Hospice of the Grand St. Bernard. In M. Mudge, N. Ryan and R. Scopigno (eds.) Proceedings of 6th International Symposium on Virtual Reality, Archaeology and Cultural Heritage (VAST2005): 29-39. Geneva, Eurographics Association.

The applet displaying the PTM above is based on an applet available at http://materialobjects.com/ptm/. The additional programing was carried out by David Potts (ACRG).