Patent ID: 7567728
Filing Date: 2009-07-28
Classification: G06T,H04N

Abstract:
1. An image transformation method, comprising: performing a coordinate transformation to transform a picked up image that is picked up by a pickup unit having an optical axis tilted by an arbitrary angle with respect to a reference plane, into an image substantially equivalent to a picked up image that is picked up by the pickup unit in a state where the optical axis of the pickup unit is perpendicular to the reference plane; and substituting luminance values of coordinates before the transformation as luminance values corresponding to coordinate values after the transformation, wherein said performing a coordinate transformation comprises: and where α denotes a tilt angle of the optical axis of the image pickup unit with respect to an axis perpendicular to the reference plane, β denotes an angle formed by a straight line that is a projection of the optical axis on the reference plane and a reference axis (x-axis) of the reference plane, γ denotes an angle formed by a tilt direction of the image pickup unit on the picked up image and a reference axis (X-axis) on the picked up image, (X, Y) denotes the coordinates on the picked up image, and (x, y) denotes the coordinates on the reference plane, wherein the formulas are successively calculated to obtain the coordinates (X, Y) before the transformation corresponding to the coordinates (x, y) of the picked up image after the transformation; and where the image transformation method is to be implemented by a computer.