Research On Information Hiding Algorithm Based On Halftone Screening

Digital halftone technology characterized the original continuous-tone images bycontrolling the pattern of halftone dots. By some algorithms the halftone screeningtechnology can be applied to the anti-counterfeiting and information hiding field with thisdots’ feature. This method is different from the general anti-counterfeiting approachswhich require the special inks and other specialized image processing tools, that can beable to loading the information through the screening process by modulating the pattern ofdots.itself encrypted. This method greatly reduces printing costs, and the securityperformance has been greatly promotion.This method studies on the image halftone process combining moderncommunication technology, by scrambling the plaintext information using pseudo-randomprocess at first, then mapping the ciphertext information to the original continuous-toneimage, at last modulating the dot shape and position to characterize the correspondinggray level to complete the screening and information hiding. In order to get the extractedinformation without the need to scanning the whole halftoned image, then blocking theplaintext information before halftone screening, and marking the sub-blocks during thescreening proces. So that the decryption information can be extracted according to themarked points in real-time scanning. This method improved the efficiency of the readinginformation and the practical level. Appled this method to the actual production ofanti-counterfeiting can obtain economic, environmental, high safety performance andother characteristics.