Patent ID: 7680301

Claim:
A method of determining a location within an environment having a known geometry, the method comprising the steps of: (a) determining a 3-dimensional location of an object not residing on the known geometry using the known geometry and only one video image, the one video image including an image of the object and at least a portion of the known geometry, said step (a) including the steps of: (a1) receiving a selection of a first image point from the image, the first point corresponding to a position of the object shown in the image, (a2) receiving a selection of a second image point from the image on the known geometry shown in the image, the second point being a projection of the object shown in the image onto the known geometry shown in the image, (a3) calculating a first ray in 3-dimensional space from a camera from which the one video image was captured in the direction of the object in 3-dimensional space, (a4) determining a first real world point on the known geometry corresponding to the real world coordinates of the second image point, (a5) calculating a second ray extending in a known direction from the first real world point determined in said step (a4), and (a6) calculating a second real world point on the first ray that represents the point of closest approach of the first ray to the second ray, the second real world point representing the 3-dimensional location of the object in the environment; (b) converting the 3-dimensional location of the object determined in said step (a) to a position of the object in the one video image; and (c) modifying the one video image based on the position of the object identified in said step (b) in order to emphasize the object in the one video image.