An improved reversible watermarking scheme

In this paper, we propose an improved high capacity reversible watermarking scheme with capacity control. By introducing reversible contrast mapping (RCM) transform and difference expansion (DE) technique into our scheme, a compressed location map indicating watermarking locations is not needed. The proposed scheme explores important features of DE embedding and takes the advantage of RCM transform to embed a few indicative flags instead of the location map for DE embedding. It improves the distortion performance at low embedding bit-rate and solves the capacity control problem. The scheme can also achieve high capacity.