Data hiding of digital images based on bit position and parity bit

Data hiding in binary images is difficult since only 1 bit is used to represent 1 pixel and distortion is conspicuous. In this paper, we propose a data hiding method in binary images by checking the bit position and parity bit to hide a secret bit in binary images. The cover image is divided into MxN sub-blocks and the parity bit of sub-block pixels are referenced to embed a secret bit for the suitable pixel. By finding the suitable pixel position to insert a secret bit for each sub-block, the image quality of the stego-image can be improved, while maintaining a low computational complexity. The experimental results show that the proposed method has a higher capacity and better visual quality as increasing a size of sub-block.