Interpolating between computerized three-dimensional forensic facial simulations

The shape of the skull is a limited predictor of facial appearance and facial reconstruction methods can offer at best a resemblance to the individual during life. Various unknown factors in addition to those relating to age, build, obesity, ethnic group, and the varying shape of the eyes, nose, and mouth mean that a variety of facial reconstructions could be produced from any single skull. A disadvantage of both traditional "plastic" facial reconstruction methods and existing computerized equivalents is that the finished reconstruction is fixed and substantial further work is required if a modified outcome is to be presented. An advantage of computerization is that if offers a greater potential for easy revision of images. Here we describe a method for interpolating or "morphing" between virtual images of facial reconstructions produced using the "plastic" technique which enables the interactive fattening of the face in three dimensions. Morphing is achieved using qmorf, a demonstration program, and using the interpolator node of virtual reality modeling language (VRML).