An image encryption scheme based on digital fractional Fourier transform and chaos theory

This research presented an image encipherment technology adopting the fractional Fourier transform and chaos theory. To expand the key space of the encipherment protection technology, we adopt the sampling digital fractional Fourier transform instead of traditional digital Fourier transform. Then, the improved double random phase masks are proposed to achieve the goal of making the encryption result close to the noise image and solve the problems of large key storage space. Based on the above works, we designed an image encryption scheme and the specific implementation details are given. In order to prove the validity and security of our designed encryption algorithm, we analyzed the effectiveness of the designed encipherment algorithm in four aspects through several experiments. The results proved that the designed image encryption algorithm not only has outstanding key safety level and great anti-statistical attack ability, but also has great anti-data loss ability and anti-noise ability.