Watermarks based on Pyramidal Images for Tampering Image Self-Restoration

This article presents the Pyramidal Image Water-marking (PIW) and Pyramidal Image Restoration (PIR) algorithms based on a pyramidal image representation. The PIW algorithm watermark a digital image with an array of compressed images corresponding to a pyramidal representation and the PIR algorithm is capable of performing automatic image restoration using the watermark images computed by the PIW algorithm. The use of pyramids avoids the quantization procedure for the reference information bits and allows us to identify pixels erroneously deemed as altered by the block-wise tampering detection scheme. PIW and PIR outperform some state-of-the-art algorithms used for automatic image restoration and can reconstruct images with a tampering rate of up to 0.95.