A Review on Encryption and Decryption of Image using Canonical Transforms & Scrambling Technique

Data security is a prime objective of various researchers & organizations. Because we have to send the data from one end to another end so it is very much important for the sender that the information will reach to the authorized receiver & with minimum loss in the original data. Data security is required in various fields like banking, defence, medical etc. So our objective here is that how to secure the data. So for this purpose we have to use encryption schemes. Encryption is basically used to secure the data or information which we have to transmit or to store. Various methods for the encryption are provided by various researchers. Some of the methods are based on the random keys & some are based on the scrambling scheme. Chaotic map, logistic map, Fourier transform & Fractional Fourier transform etc. are widely used for the encryption process. Now day’s image encryption method is very popular for the encryption scheme. The information is encrypted in the form of image. The encryption is done in a format so no one can read that image. Only the person who are authenticated or have authentication keys can only read that data or information. So this work is based on the same fundamental concept. Here we use Linear Canonical Transform for the encryption process

An Experimental Approach for Encryption and Decryption of Image using Canonical Transforms & Scrambling Technique

Data security is a prime objective of various researchers & organizations. Because we have to send the data from one end to another end so it is very much important for the sender that the information will reach to the authorized receiver & with minimum loss in the original data. Data security is required in various fields like banking, defense, medical etc. So our objective here is that how to secure the data. This study is performed on MATLAB R2016b with standard databasegrey scale images like Barbara, Cameraman and Lenna or by using the personalize images in standard format. First of all, the images are scrambled and then the generation of a new complex image took place. Initially phase mask is applied on the complex image by using RPM 1, and then the complex image is encrypted by using LCT of first order. Again the phase mask RPM 2 is applied on the encrypted image followed by the LCT of second order to get the encrypted image finally. Reverse process is applied to get the original image. Various parameters are calculated which shows various aspects. Like Change in the value of MSE with change in order of transform tells the quality of encrypted image. Correlation coefficient of encrypted and decrypted image also shows the difference between the encrypted and decrypted image. The original image is then reconstructed and histogram of all these images analyzed. Robustness and imperceptibility of images increases by the proposed method

Optical image compression and encryption methods

International audienceOver the years extensive studies have been carried out to apply coherent optics methods in real-time communications and image transmission. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. However, the transmitted data can be intercepted by nonauthorized people. This explains why considerable effort is being devoted at the current time to data encryption and secure transmission. In addition, only a small part of the overall information is really useful for many applications. Consequently, applications can tolerate information compression that requires important processing when the transmission bit rate is taken into account. To enable efficient and secure information exchange, it is often necessary to reduce the amount of transmitted information. In this context, much work has been undertaken using the principle of coherent optics filtering for selecting relevant information and encrypting it. Compression and encryption operations are often carried out separately, although they are strongly related and can influence each other. Optical processing methodologies, based on filtering, are described that are applicable to transmission and/or data storage. Finally, the advantages and limitations of a set of optical compression and encryption methods are discussed

Image Cryptography using Parameterized Multiband Eigen Wavelet Filterbank

In this paper, we present an eigen filterbank based approach for image cryptography. The proposed method consists of designing a wavelet filterbank using eigenfilter based approach and use the designed filterbank for image encryption with new methodology. We have extended an eigenfilter based approach for the design of multiband two-channel filter bank. This method is based on designing multiband analysis filter, followed by the design of complementary multiband synthesis filter. The designed filterbank has various user defined parameters (key) like, number of bands in the filter spectrum, cutoff frequency of individual frequency band and the level of decomposition. Based on the selection of these parameters we can design a unique filterbank, which can be used for the image encryption. At the decryption end, the original image can be reconstructed only if user selected parameters are known. We present few design examples for the illustration purpose. We also give detail of complexity analysis of the entire cryptography system and also present the time analysis. The proposed approach provides more number of user parameters as compared to state-of-art methods, which can be used as more secure key. It is also observed that the computation time of the proposed approach is comparable