A Zero-watermarking Algorithm of SVG Vector Map Based on Stroke-width Characteristic

This paper proposes a zero-watermarking algorithm of SVG vector map based on stroke-width characteristic. The algorithm takes the stroke-width as an important characteristic. By statistics, calculating and simplifing the stroke-width probability in SVG vector map, building a K-d characteristic vector. With the Arnold transformation and specific operation, the stroke-width characteristic vector is embedded in the original watermark image, that is the zero-watermarking. Because the algorithm doesn't modify any coordinates, common operation such as geometry editing, geometry transformation, data compression and coordinate precision reduction doesn't affect the watermark extraction. Because of the simplification of stroke-width probability, the deletion of a small amount of entities has no influence on the extraction of the watermark yet.