Reversible Data Hiding Scheme for Color Image Protection Based on Palette Color Replacement

In this paper, a novel reversible data hiding scheme is proposed to embed the color information of a palette image into its corresponding grayscale image by using the palette color replacement. Using the proposed scheme, two different qualities of images can be provided, they are the grayscale image and the color image, one for free access, and another for limited access, respectively. The proposed method reordered the palette colors according to their occurrence frequencies in the image and repeated performing a palette color replacement procedure to embed enough information into the grayscale image. Consequentially, we can reconstruct the palette color image by extracting the embedded information from the marked image. The performance of the proposed method is demonstrated by showing the good qualities of both the marked and the rebuilt images.