A novel watermarking schem using directionlet

In this paper, a new robust digital image watermarking algorithm is proposed in Directionlet transform domain. Directionlet transform (DT) is able to capture the directional edges and contours superior to many multi-resolution geometric analysis (MGA) tools. At first, sample the original image with the generator matrix; Then, decompose each coset into the subbands with directionlet transform. For embedding watermark bits, We select a M×M coefficients from the middle frequency domain of all the cosets of the lattice, as many as bits of the binary watermark image. The experimental results show that the proposed algorithm has a good resistance against to common attacks,moreover it outperforms previous methods in the most situations.