| dc.description.abstract | Abstract
Any digital information can be transmitted widely by internet as Internet become universal. It implies that the digital techniques make that life become convenience. However, there are some potential issues, e.g., private, copyright protection, information copy, tampering, and so on. Therefore, how to protect the digital data transmitted on Internet becomes an important issue.
Recently, information security techniques have been proposed continually, e.g., cryptography, secret sharing, and data hiding. Each information security technique owns different advantages and disadvantages. For example, a sender used key to encrypt digit information as cipher. After transmitting cipher to receiver, `the information can be decrypt to obtain secret data. Although hackers do not have key to decrypted data, he/she can intercept or destroy data, making that receiver cannot obtain correct information.
In order to solve this problem, many scholars proposed the concepts of data hiding. In this paper, a difference encode method is proposed to embed more secret data, where the secret data is large. The proposed method used local and global characteristic to transform most secret data into the smaller values. On contrary, a few secret data are converted into the larger values. Since embedding the smaller value does not invoke serious image distortion, the proposed method has better image quality than the previous method with the same embedding ratio.
Keyword: Data hiding, Absolute moment block truncation coding, PSNR, difference expansion | en_US |