procedure for determination of the kippwinkels and positioning of a document in a scanned image

摘要

A method for determining skew angle ( 5 ) and location of a document in an over-scanned digital image is disclosed. A document is scanned to capture a gray scale image. The outline pixel ( 1 ) of a document from the captured gray scale image are connected ( 2 ). An initial angle is set at zero and a x-minimum, y-minimum, x-maximum, and y-maximum of the polygon are determined ( 3 ). A rectangular boundary ( 4 ) area based on the x-minimum, y-minimum, x-maximum, and y-maximum is calculated and recorded. The angle is recorded and the polygon is rotated z-degree. The process is repeated and a minimum boundary area is selected. An angle corresponding to the minimum boundary is the skew angle of the document.