Patent ID: 7256782

Claim:
A method for compositing a computer-graphics image and a picture taken by a camera comprising: defining, in accordance with conditions in which the picture is taken, a three-dimensional model, a viewpoint, and a plane of projection, in a space established on a computer, the conditions comprising at least one of the tilt angle of the camera relative to a ground surface and the position of a light source relative to the camera; defining lines of sight extending from the viewpoint to projection pixels on the plane of projection so that each of the lines of sight conforms with a ray of light incident on a pixel corresponding thereto of the picture taken by the camera; tracing the lines of sight extending from the viewpoint through the plane of projection and the three-dimensional model to obtain attributes of portions of the three-dimensional model corresponding to the projection pixels, thereby forming a two-dimensional image of the three-dimensional model on the plane of projection; and superposing the two-dimensional image on the picture to generate a composite image; wherein said step of defining lines of sight involves providing a calibration table having first data and second data correlated with each other, the first data comprising positions of pixels of the picture taken by the camera and the second data comprising calibration data corresponding to directions and positions of rays of light incident on the pixels of the picture, wherein the lines of sight are obtained by looking up the second data by the first data in the calibration table.