A small team of researchers from the University of Cambridge have created a program that enables users to build virtual 3D models of textured objects in-real time, using only a basic webcam and computer. Constructing a virtual 3D model usually takes a huge amount of time and effort, and requires expensive, specialist equipment. However this new program makes 3D modeling accessible to everybody. Over the past few years, numerous methods have become available which allow the user to build a realistic 3D model from a real thing. Things such as, projectors, 2D/3D lasers, scanners and cameras have been used in recent years. This equipment is quite costly for small businesses, and can be extremely complicated to use for the user.  With some equipment the data must be acquired before it can go through the lengthy, tiresome reconstruction process to form the visual model.  Problems can then arise if the 3D reconstruction isn’t acceptable, which means the user must then reenter all the data. The three researchers, Qi Pan, Dr Gerhard Reitmayr and Dr Tom Drummond proposed their new method using a very simple web cam and won ‘Best Demo Prize’ at the ISMAR (International Symposium of Mixed and Augmented Reality) 2009 conference.  The program works when an object is moved around slowly in front of the web cam. The software reconstructs the object while recording the live video. The software uses a collection of points that are detected on the object and estimates the objects structure from the motion of the object or camera, it then computes the ‘Delaunay tetrahedralisation’ of the points (the extension of the 2D Delaunay triangulation to 3D.) The points collected are then recorded into a mesh of ‘tetrahedra’, within which the surface mesh of the object is embedded. The program then has the capability to clean up the final recorded reconstruction by removing the invalid tetrahedra to obtain the surface mesh based on an estimated carving algorithm, then the objects texture is applied to the 3D meshing in order to create a realistic looking model. This simple to use and cheap software could pave the way for many more people to become interested in 3D reconstruction and virtual modeling. Source: physorg.com