A New Watermarking Scheme for CAD Engineering Drawings

So far most watermarking Schemes focus mainly on common dot image, audio, video and text. Studies on the watermarking of vector graphics especially the 2D vector engineering drawings have only just begun. This paper proposed a novel watermarking technique for 2D engineering drawings, which is based on Modulus operation and Hopfield network. Watermark is embedded proportionately into the lengths of lines from an engineering drawing via Modulus calculation and can be extracted without exploiting the original engineering drawing. To improve the security of watermarking, we preprocess the watermark data using Arnold transform before embedding. By means of Hopfield network the extracted watermark can be further recovered and amended effectively. Experimental results show the proposed watermarking scheme is almost completely robust to rotate, scale, transplant (RST) as well as their combinations, and also strong enough to cropping attacks.