Information hiding based on binary encoding methods and pixel scrambling techniques.

Novel information hiding for digital images based on binary encoding methods and pixel scrambling techniques is presented. First, a pixel scrambling technique is used to rearrange the pixels of a covert image to form a scrambled matrix by using a specified scrambling rule. Then, the gray values of all the pixels in the scrambled matrix are sequentially transformed into many sets of eight-digit binary codes. Subsequently, the eight-digit binary codes are encoded into a host image to form an overt image by using a specific encoding rule. Besides the eight-digit binary codes (information codes), the overt image contains five other groups of binary codes (specification codes), i.e., identification codes, gray-level codes, dimension codes, scrambling number codes, and scrambling time codes, to denote the parameters used for scrambling and encoding. According to the test results, the proposed method performs well. Moreover, the overt image and the host image look almost the same, and the decoded covert image is exactly the same as the original covert image.