Multimedia Data Hiding and Authentication Via Halftoning and Coordinate Projection

We present novel image data hiding and authentication schemes based on halftoning and coordinate projection.The proposed data hiding scheme can embed images of the same size and bit depth into the cover image
and robustness against compression is demonstrated.  The image authentication scheme is based on the proposed data hiding scheme and can detect, localize and repair the tampered area of the image. Furthermore, the self-repairing feature of the authentication scheme has a hologram-like quality; any portion of the image can be used to
reconstruct the entire image, with a greater quality of reconstruction as the portion size increases.