A reversible watermarking for authenticating 2D CAD engineering graphics based on iterative embedding and virtual coordinates

Aim to authenticate the integrity of 2D CAD engineering graphics, a reversible watermarking method based on iterative embedding and virtual coordinates is proposed. For each vertex in 2D CAD engineering graphics, two neighboring virtual coordinates are generated to form an embedding data unit, which is good for the improvement of the correlation of them. Meanwhile, iterative embedding policy is implemented to enhance the capacity. Experimental results and analysis show that it is strictly reversible, and the capacity is positive proportion to the embedding times. Meanwhile, the distortion can be well controlled in a small range, and it is robust against translation and scaling. It has potential application in the integrity protection of 2D CAD engineering graphics with low correlation and high data precision requirements.