Patent ID: 6643396
Filing Date: 2003-11-04
Classification: G01C,G06T,H04N

Abstract:
A method of acquiring a three-dimensional scene using a single hand held camera having a lens, attached to a lens attachment comprising a right and a left inner mirror, both inner mirrors being located in front of the lens facing inwardly along an optical axis of the lens toward the lens, covering substantially all of a field of view of the lens, the inner mirrors being connected together at one edge at the optical axis of the lens, such that the two inner mirrors form an acute angle symmetrical about the optical axis of the lens, a right and a left outer mirror, both being larger than the inner mirrors and located outward of the inner mirrors, facing outward toward the subject, such that substantially all of the field of view of the inner mirrors is covered by the outer mirrors, the outer mirrors being pivotable about a vertical axis, a ganging mechanism for simultaneously pivoting the outer mirrors about their vertical axes in opposite senses, having a control input for actuating the ganging mechanism, such that a movement of the control input causes the right and left outer mirrors to pivot equally, oppositely and simultaneously, such that a movement of the control input in one direction causes the fields of view of the outer mirrors to converge, and a movement of the control input in the opposite direction causes the fields of view of the outer mirrors to diverge, and an adapter for moving the control input of the ganging mechanism in response to actuation of a focusing means of the lens, connected to the control input of the ganging mechanism and the focusing means of the lens, such that when the lens is focused at a selected distance, the field of view of the outer mirrors converges at the selected distance, wherein the field of view of the lens of the single camera is split into two virtual cameras, each with half of the field of view, comprising the steps of:a) deriving values for a, b, and w by performing a fixed calibration for at least one value of a convergence angle (&Dgr;&agr;) and at least one focal distance (f) wherein w is defined as a distance between an optical center of the single hand held camera and an optical center of each of the virtual cameras, and a and b are parameters estimated to establish a relationship between w and h, wherein h is a distance between the optical center of the single hand held camera and an intersection of the two inner mirrors; b) recording an image of a scene using the single hand held camera and the lens attachment; c) processing the recorded image using the value for the convergence angle (&Dgr;&agr;) and the focal distance (f); and d) storing a processed three-dimensional image.