A Fast and Efficient Data Hiding Scheme in Binary Images

Several data hiding techniques have been proposed in the literature in recent years for binary images. However most of them suffer from image distortion. One such data hiding technique introduced in [7] is based on optimization and dynamic programming. The technique uses block pattern encoding and the resulting images not only contain more data bits, but are also shown to be optimally distortion minimizing. Although the technique is quite effective and produces good results, time taken in encryption is abnormally high with O(n²) complexity. In this paper we have proposed a simpler method for data hiding in binary images that reduces the time complexity of the algorithm to O(n) while keeping the distortion low. We use a twofold encryption by inserting the data in the image using block pattern encoding table similar to [7] and then using XOR operation to increase the security of the data. The proposed algorithm follows a greedy approach which takes into consideration the local minimum cost of bit replacement leading to a significant difference in the execution time.