Research On Panoramic&Information Encryption And Its Application In Public Security

Due to the security situation been more and more serious, especially in High-levelrisk areas, panoramic and encryption technology has become an urgent requirement.Dissertation “Research on Panoramic&Information Encryption and its Application inPublic Security”, panorama theory and information security technology are combined,and the security scene mosaic and the image encryption theories are used in securityimage fragments. It has important theoretical significance and practical value.Firstly, the key steps in Panorama mosaic are mainly image preprocessing, imageregistration and image fusion. The second step is the base and key of mosaictechnology. The paper studies above steps about special application in security imagefragments. SIFT is a kind of feature point registration algorithm. It remains invariantfor scale transformation, rotating, brightness change, and good stability. So it iswidely used in image registration. But the feature description vectors in SIFT is128dimensions, which causes large computation complexity of corresponding matchingalgorithm has and lower efficiency. In this paper, an improved SIFT algorithm isproposed to reduce the dimension from128d to48d by using circular rotationinvariance. It improves the extraction speed of feature point and reduces thecomputation complexity of feature matching. To match the feature point, a matchingalgorithm based on modulus is used, which includes limiter, normalization, andmodulus calculation. And then the difference with the similarity matching modulus iscalculated so as to determine matching pairs through limiting difference. Comparedwith normal NN algorithm, the computation complexity of this method is decreasedand matching efficiency is improved. To Image fusion overlap region, a nonlinearweighted fusion algorithm is used, which can effectively eliminate the patchwork andghosting and ensures consistency of image brightness.Secondly, the importance and the performance indexes of image encryption areshown. The fundamental knowledge of cryptography and chaos theory as well aschaotic cryptography and its development are analyzed. Then the following two kindsof encryption algorithm are compared:(1) A traditional image encryption algorithmbased on Logistic chaotic system is given. By analysis algorithm principle, designalgorithm steps and test the safety and efficiency in security image, the analysis andtests show that the local performance is good whereas the overall effect is not suitable for encryption of the system.(2) Image encryption algorithm of scrambling anddiffusion based on multiple chaotic systems is proposed. The control parameters ofscrambling and diffusion are produced by Logistic and Kent mapping. The scramblingand diffusion of the gray value are realized by Arnold mapping and the modularaddition. The tests results indicate that this algorithm meets the basic security andreal-time requirements of the system. The experiment results show that, the improvedmulti-chaotic encryption algorithms has large key space and key sensitivity, whichcan effectively resist the exhaustive analysis of the attack; encrypted pixel graydistribution, weak correlation of adjacent pixels can effectively statistical analysisresist attack. Alternated2generations, the NPCR and UACI can achieve the desiredfor anti-differential attacks. Compared with the traditional encryption algorithms, theimproved multi-chaotic encryption algorithm has high encryption efficiency.At last, in order to solve the problems that panoramic inspection and imageencryption application in security protection,"panoramic image of security andencryption systems" was designed. It included hardware acquisition of smart car andpanoramic image of security and encryption software. The application testing showthat, experimental prototype have important theoretical significance and applicationvalue.