Patent ID: 7808513

Claim:
A system, comprising: a projector including an interface configured to: display a pattern set on a projection surface separate from the projector, where the pattern set comprises a plurality of partially overlapping polygons and each polygon is different from the remaining polygons in one or more of shape and rotation such that each of the plurality of polygons corresponds to a different combination of horizontal rotation angle and vertical tilt angle of the projector with respect to the projection surface; and receive a selection from a user of a selected polygon in the pattern set, where the selected polygon comprises an entire polygon and represents a minimum amount of keystone distortion as compared to the remaining polygons in the pattern set; and a controller in the projector to distort image data dependent upon which of the plurality of polygons is selected by the user and the horizontal rotation angle and vertical tilt angle corresponding to the selected polygon, wherein the controller is configured to distort the image data by vertically scaling the image data using the function f 2 , where: f ⁢ ⁢ 2 = eqnV = ∑ j = 0 b ⁢ ⁢ ( VDN 2 16 + a × VDNPI 2 16 + j × VDNI 2 16 ) + ( YO + a × YI 2 16 ) . ⁢