Measuring the surface area of the face

A noncontact, biologically safe imaging system for measuring surface area and volume is described. It uses a technique known as structured light, a method in which the surfaces of 3-D objects are measured by projecting a regular geometric pattern onto its surface and viewing the illuminated surface using one or more cameras at different angles. The 3-D locations of points on the surface of the skin are reconstructed from the structured light, and the region of interest is segmented. After the reconstructed 3-D locations and the segmented image are combined, cubic spline interpolation is used to represent the space curves and bicubic surface patches to represent the surface area. Gaussian quadrature double integration is used to calculate the surface area. The steps necessary to do the segmentation, curve and patch representation, and surface area computation are outlined. It is found that the surface area estimates are as accurate as estimates based on visual inspection