Extraction of Answer Image of Choice Questions in Examination Paper.

firstly, the skewed image of examination paper is corrected by Hough transform, and then mathematical morphology methods are used to locate the frame lines in table. Then connected component analysis is utilized to locate the form region based on maximum area feature. Finally the form frame line is removed according to the vertical gradient, and the answer image is achieved by analyzing the coordinates of objects. [ABSTRACT FROM PUBLISHER]