Using of an Arithmetic Sequence to Estimate Undetected Existing Circle Choice Locations

Abstract

Handling an optical mark recognition (OMR) answer sheet faces a problem of shape detection due to defections of color, resolution and shape. A typical method of shape detection thus creates false detection. The false detecting problem is that the general detecting approach fails to detect the locations of the filled shape or detects only the previous detected locations. For this work focuses on a circle choice shape. To solve such problem, an arithmetic sequence is proposed to estimate the existing circle-shaped locations undetected by the common detecting scheme. The proposed technique is verified by experimenting the OMR answer sheet having thirteen options per item. Two conditions are experimented. The first condition arbitrarily fills a circle in each item and the other one leaves the circle in each item unfilled. The experimental results have revealed that the average success rate of the proposed approach in locating the undetected existing circle shapes is 100% for both conditions.