Developments in steganography

Abstract

This paper presents two main results. The first is a new approach to steganography in which data is encoded in correlations among the pixels in an image. Almost all previous steganographic methods encode data in correlations between the pixels and a known external reference signal. This method hints at the existence of public key watermarking techniques, which will be defined. The other result is a method for greatly increasing the capacity of a printed steganographic channel. Because it is specific to printed images, this method is useful for steganographic problems such as stealth barcoding, but not for digital watermarking. The two results are complementary in that higher noise levels are encountered in the intra-image correlation encoding method, but the second method works by eliminating imageinduced noise.