A reversible watermarking scheme for 2D vector drawings based on difference expansion

This paper proposed a reversible watermarking scheme for 2D vector drawings based on difference expansion DE. Few researches have been conducted on reversible watermarking method of 2D vector drawings till now. In our scheme, Information data including watermark is embedded into the nearest pairs of vertexes sequence in x-direction or in y-direction instead of the pairs of neighbouring vertexes, and as a result the capacity of watermark will be increased and shape distortions be reduced. The Hash value from the original drawings is also embedded as a part of watermark in order to exactly estimate the completeness of the extracted data. Experimental results demonstrate that the proposed reversible watermarking algorithm can accurately separate and completely extract the watermark as well as host data. Generally it shows better performances than the previous ones.