Three-dimensional modelling using X-ray shape-from-silhouette

We present the application of the shape-from-silhouette technique to reconstruct the three-dimensional profile of ancient handworks from their x-ray absorption images. The acquisition technique is similar to tomography, since the images are taken all around the object while it is rotated. Some reference points are placed on a small and light structure corotating with the object, and are acquired on the images for calibration and registration. The reconstruction algorithm gives finally the three-dimensional appearance of the handwork. We present the analysis of a bronze pendant of VI-VII century B. C. (Venetic area, Italy) completely hidden by corrosion products. The three-dimensional reconstruction shows that the pendant is a very elaborated piece, with two embraced figures that were completely invisible at the excavation.