Rotationally robust data hiding in JPEG images using a tunable spreading function

Digital media is incredibly easy to create, store, copy and manipulate. For these reasons it is desirable to authenticate, trace and otherwise fingerprint digital media at the point of origination. These objectives can be accomplished by digital watermarking whereby a digital signature is embedded in imperceptible portions of cover media. Since the marked media may undergo friendly operations such as filtering, compression and scaling the watermark must be robust. One of the more difficult operations that the digital watermark must survive is geometric manipulation. In this paper we present a digital watermarking algorithm that can survive the combined compression/rotation attack and still remain detectable