Adaptive message embedding in raw images

Abstract

In this paper, we propose an adaptive approach to message embedding in raw images. The cover image is divided into blocks where the top left pixels are dedicated as control pixels used to identify blocks carrying message information. Message bits are embedded while restricting the number of pixel changes in a cover segment to one change only. This is achieved through a concept of overloading the embedding indices; therefore, a maximum of one pixel value is changed per block for message embedding. The proposed solution is assessed in terms of percentage of changed pixels, PSNR, SSIM, histogram changes, and blind steganalysis. Comparison with existing work reveals that the proposed solution reduces both the image distortions and pixel change rates. It is also shown that the proposed solution is less detectable when tested with blind steganalysis in comparison to existing solutions.