Secret data hiding by optimizing general smoothness difference expansionbased method

Computer network has made it easy to exchange data; however, there is a security challenge raising from it. This is because the transmitting data can be intercepted by an attacker. Steganography can be used to prevent an attacker from exploring the information in the intercepted data. There are three common problems in the steganography, those are: obtaining both secret data and cover data from stego data, capacity of the secret data and the quality of the stego data. In this paper we propose a method which works on those problems based on the smoothness difference expansion. The experimental result shows that the proposed method is able to extract both secret and cover data, to increase both capacity and quality of the stego data.