A new judgement method used in information hiding system

The paper presents a new judgement method that can be used in an information hiding system. Generally, signal-to-noise rate (SNR) is used to judge transparency; a similarity measurement is used to determine to which degree the extracted information is similar to the original message. From the view of probability theory, a mean cost is proposed to reflect the loss of the information-hiding system. It is in negative proportion with the threshold of the similarity measurement and the length of the message. Experimental results show that the mean cost is beneficial to specify the threshold of similarity measurement and the message length.