An Improvement of Square Matrix Encoding by Adjusting Digits in a Matrix

The proposed method was derived from Chen’s Square Matrix Encoding for information hiding. Square Matrix Encoding is modified from Diamond Encoding by changing a diamond matrix to a square matrix. The image distortion is reduced when the secret data were embedded by using the square matrix. In order to further improve the security and reduce image distortion, this paper proposes a mechanism to adjust the digits in the square matrix according to a given cover image and secret data. By employing the adjusted-square matrix, good quality stego images can be achieved. According to experimental results, the Square Error values between the stego images and the cover images in the proposed method are lower than those in the other two methods. The proposed method is thus superior to both Diamond Encoding and Square Matrix Encoding.