Exclusively from Cambridge: Creating 3D models with a simple webcam
Yet another great discovery to join the University of Cambridge’s cabinet of fame as researchers at the Engineering Department created a program able to build 3D models of textured objects in real-time, using only a standard computer and webcam. Up to this point, the construction of virtual 3D models usually required heavy and expensive equipment, was time-consuming and complicated to use or inconvenient and the model was not built in real-time. The existing methods for capturing 3D models range from 2D/3D laser, (in visible spectrum or other wave lengths), scanner, projector, camera, etc. The data (for example laser information or photos) must first be acquired, before going through the lengthy reconstruction process to form the model. If the 3D reconstruction is unsatisfactory, then the data must be acquired again.
The new method for capturing 3D models needs only a simple webcam. The object is moved about in front of the webcam and the software can reconstruct the object “on-line” while collecting live video. The system uses points detected on the object to estimate object structure from the motion of the camera or the object, and then computes the Delaunay tetrahedralisation of the points (the extension of the 2D Delaunay triangulation to 3D). The points are recorded in a mesh of tetrahedra, within which is embedded the surface mesh of the object. The software can then tidy up the final reconstruction by taking out the invalid tetrahedra to obtain the surface mesh based on a probabilistic carving algorithm, and the object texture is applied to the 3D mesh in order to obtain a realistic model. Thanks to this simple and cheap system, 3D reconstruction can become accessible to everybody.
Demonstration of what the new 3D modelling method requires and how it should be used can be viewed here.