Interactive operation on 3D real images using ray description

In the field of 3D visual communications, a method of description of 3D images that would be neutral (independent) with respect to specific techniques for 3D input–output is desirable. In this context, the authors have proposed the concept of “ray-space” as a ray-based description method for 3D image data. In this paper, the concept of “ray-space” is employed to offer a new method for simultaneous description of 3D objects and space, as well as a technique for interactive manipulation in virtual space built using real images. Synthesis of images as seen from an arbitrary viewpoint in real space means extraction of ray data on a curved surface described by some basic formula in ray-space, using information about the viewpoint location. In this study, real-time processing is pursued; for this purpose, a reference table is employed for efficient extraction of ray data. Experiments were carried out concerning virtual manipulation of real objects in near-real time by means of overwriting ray-space data with ray data of the 3D object under consideration. The experiments confirmed that the proposed method offered efficient description of 3D space data and object manipulation. © 1999 Scripta Technica, Syst Comp Jpn, 30(14): 12–22, 1999