Research On Multi-spectral Remote Sensing Image Encryption Based On Composite Chaotic System

With the deepening of Internet application,the attack mode of multimedia information is also developing,the protection of multimedia information has become one of the important research contents in the field of information security and cryptography.As an important space-time data,remote sensing image is not only large in data,but also has the characteristics of multi-temporal phase,multi-precision,multi-band,high resolution,etc.,and has been widely used in agricultural production,weather forecasting,geographical survey,land planning,environmental monitoring,disaster prediction and other important fields.As a special digital media,remote sensing image has not only the characteristics of digital image,but also has the need of encryption different from the general digital image,so it is necessary to study the encryption of remote sensing image.Chaos is an unpredictable pseudo-random phenomenon in deterministic systems that is sensitive to initial values.Because the chaos dynamic system has the characteristics of pseudo-randomness,uncertainty and extreme sensitivity to the initial parameters,and has many similarities with cryptography theory,it is feasible to apply the chaos system to image encryption.Based on the composite chaos system,a double encryption algorithm for image-based encryption and pixel value encryption is proposed,and on this basis,an image encryption algorithm based on complex chaos system and key generation for multispectral remote sensing images is proposed.The main research work in this paper is as follows:(1)based on chaos theory,a picture encryption algorithm based on the combination of Logistic chaos system and Henon chaos system is proposed.The algorithm uses the pseudo-random sequence generated by the composite chaos system to encrypt the digital image and the pixel value.Experiments show that the encryption algorithm proposed in this paper makes up for the complexity of operation,inefficient,not suitable for non-square images,has periodic security problems,can not resist statistical analysis and other shortcomings,compared with the image encryption algorithm based on half-volume accumulation proposed in recent years,although the encryption efficiency is not high.But it can withstand attacks such as modification and tailoring,and is more robust.(2)In view of the multi-band characteristics of remote sensing image,a multispectral remote sensing image encryption algorithm based on compound chaos system and key generation is proposed.The algorithm uses the composite chaos system to generate different keys for each band's image,and encrypts and fuses pixel values separately.Experiments show that this encryption algorithm makes the image information of each band be well hidden and can resist all kinds of attacks,compared with the remote sensing image encryption algorithm proposed in recent years,there is great progress in the key space,which provides a new way of thinking for the encryption of multispectral remote sensing image.