The Estimation of the New Feature Extracting Method for Tamper Detection in Printed Documents

In this paper, we report the experimental result of the estimation of our proposed technique to extract the feature of the printed documents for tamper detection. We have compared the proposed technique which uses median points as a feature and the existing technique which uses the area of the black dots as a feature. As an experiment, we calculated the median point of alphabets and numbers, and printed and scanned to see the probability of the collision, the uniformity of the distribution, invariability during D/A and A/D transform, and the invariability during the ordinal change of paper of our feature extracting method. For the probability of the collision, the proposed method showed lower probability of the collision than the existing one. For the uniformity of the distribution, the proposed method showed a half skew of the existing one. For the invariability during D/A and A/D transform, the proposed method showed the invariability of about a thirtieth of the one of the existing one. For the invariability during the ordinal change of paper, the proposed method showed an eighteenth invariability of the existing one. From the above results, we have concluded that as a feature extracting method, our proposed method is better than the existing one.