Information Hiding Based on Image Morphing

Recently, we proposed a new technique for information hiding based on image morphing. Since the cover message can be changed after embedding the secret message, the cover rate of the new technique is much larger than that of existing techniques. However, this technique has two fatal problems. First, the stegodata may not look natural due to inaccurate definition of the feature lines. Second, the secret image might be estimated to some extent from the stegodata. In this paper, we propose several methods to solve these two problems. First, to make the stegodata more natural, we propose to scale down the secret message before calculating the stegodata. To solve the second problem, we propose to encrypt the secret message first, and then hide it into the warped cover image. To increase the security further, we also propose to separate the stego key and the secret message.