Lossless data hiding for electronic ink

This paper presents a novel lossless data hiding technique for electronic inks. The proposed algorithm first computes the analytical ink-curve function for each stroke as a set of smoothly concatenated cubic Bezier curves. During embedding, a set of data carrier points on the ink-curve are computed, perturbed and inserted back into the original point array together with some marker points. In extraction, data carrier points are identified and compared with their original positions in order to decode the secret message. Through experiments, we demonstrate that significant mount of secret message can be embedded and the ink-curve computed from the marked ink data closely resembles the original ink-curve.