Development of an automatic map drawing system for ancient bas-reliefs

In this paper, a new system for automatic drawing of bas-reliefs is presented. The system consists of a fringe projection scanner accompanied by a photometric stereo component. At first, the photometric stereo is used to accurately extract normals of the relief surface. Using a line tracing algorithm the normals are converted into 2D lines. Then, using the fringe projection scanner, the 2D lines are transformed to the 3D space to form a metric map required for cultural heritage applications. To evaluate the system, several tests were carried out using artificial and real bas-reliefs. The results showed that the system is able to draw 98.8% of the object lines correctly.