An Encryption Algorithm for 2D Engineering Graphics´ Content Based on Chaos Systems

An encryption algorithm is proposed for 2D engineering graphics´ content based on Logistic mapping and Tent mapping. The vertices´ coordinates are extracted from 2D engineering graphic at first, then they are confused according to the order of chaos sequences, which are generated by chaos systems. After that, the vertices´ coordinates are replaced by multiplying the chaos sequences with a XOR value, which is gained by XOR the integral part of the average of the two neighboring coordinates with a key block. Simulation and analysis shows that the key space is large, and the algorithm is very sensitive to the key, original graphic and encrypted graphic. After encryption, the degree of freedom of the engineering graphic has been changed greatly, at the same time, MSE, SNR and PSNR value are also analyzed. The algorithm is a good candidate for the security of 2D engineering graphics.