A novel watermarking method to construct watermark synchronism by using image specific edge and Directionlet transform was proposed. The direction of the image specific edge is selected as the transform direction of Directionlet

the alignment direction of Directionlet is achieved by forming an invariable angle with the transform direction. The generator matrix of the lattice is given by the two direction vectors.Several copies of watermark are adaptively inserted into coefficients of the selected middle and low frequency subband of all the cost of the lattice. In order to eliminate the effect of geometric attacks，the watermark is detected in the reference frame established by utilizing the direction of the image specific edge as direction of its an coordinate axis. Experimental results show the proposed watermarking algorithm outperforms the Wavelet and Contourlet-based in terms of transparency as well as robustness

especially at the geometric attacks such as rotation.