Evaluation of Digital Watermarking System for Vector Map Content Distribution

We have experimentally evaluated a previously developed line-division-based digital watermarking approach for small vector maps (around 600 vectors or less), which normally do not have enough modifiable redundant parts for implanting robust watermarks. It works by inserting vertices in the line segments, and the ratio of the internal division represents the embedded information. Our evaluation of this approach in a system showed that the invisible marks added by the system can survive routine user operations and trace content like barcodes do and that it overcomes the problems of handling small data. This enables potential users to contact the owner and request permission for reuse, thereby facilitating evolution of map content distribution