Data hiding scheme based on octagon shaped shell

Steganography is the art of hiding covert message in unsuspected digital media and is generally used in secret communication between acknowledged parties. A good approach to steganography must provide good visual quality, high embedding capacity and security. In this paper, a new data hiding scheme based on octagon shaped shells is proposed to obtain better image quality and higher embedding capacity while security is achieved by scrambling the secret image using magic square. In the proposed method, a secret digit is embedded into each cover pixel pair with the help of a reference matrix consisting of connected octagons. Experimental results show that the proposed scheme ensures higher embedding capacity and security compared with existing schemes and also provides good visual quality but also better visual perception of the stego-image.