Zero-Watermark Scheme for 2D Vector Drawings Based on Mapping

In this paper a zero-watermark scheme based on mapping was proposed for 2D vector drawings. There are few achievements in this field till now. In our scheme, the watermark is not embedded into but built or picked up from the original vector drawings by mapping the most two important characters the length ratio and angle to a dot picture which can also be saved in a vector format. Experimental results demonstrate that the proposed technique with higher accuracy and computation efficiency is lossless and robust enough against the ordinary attacks such as rotating, scaling, transplanting (RST) as well as their combinations, and even cropping and adding attacks. Moreover it has a distinctively visual effect. This scheme shows generally better performances than the previous ones and is faithful enough for the authentication.