Reversible Authentication Scheme of Images based on Lifting Wavelet Transform

A new reversible watermarking algorithm for image authentication, which embeds authentication information into the sub-band coefficients after lifting wavelet transform by using the difference expansion method, is proposed in this paper. Block map, after quad-tree decomposition, is used to represent the whole characteristic of image content and embed it into the original image as watermark information. Experiments results show that the proposed scheme can restore the image reversibly and has good ability to detect and locate vicious tamper.