New Authentication Watermarking Algorithm and Its Simulation Research

摘要

We propose a content-based semi-fragile watermarking scheme, which can be used for still images authentication. Let the original image perform the 1-level discrete wavelet transformation after encrypted base on chaotic sequences. Then use the approximation wavelet coefficient matrix of the encrypted image to generate the content-based and secure watermark. Finally the watermark is embedded into the original image in DWT domain by utilizing the technique of HVS. The tamper detection generate the new content-based watermark of the received watermarked image using the chaotic sequences, denoted as W', and the original watermark, denoted as W~*, is extracted from it. The place where the value of W~* is not equal to the ones of W' is tampered. So we can identify the tampered region. We have simulated the algorithm by using the Matlab simulation tools. The simulation experiment prove the tampered region can be exactly extracted if the watermarked image undergone the tampered.