Research Of Image Encryption Algorithm Based On The Chaotic Sequences Of Wavelet Domain

Image encryption technology is from the early classical encryption system, it is an important means to ensure the image information security transmission. It's aim is to transform a given image into a mess and no texture image by certain transformation rules in airspace or in the frequency domain, thus hiding their true image information.In recent years, the image encryption technology has developed rapidly and many image encrypt methods have been put forwarded. There have two major encryption ideas of air and transform domain. Compared to the spatial domain algorithm, the transform domain encryption algorithm has more efficient and in transform domain every point in the changes of the entire data set will certainly have an impact.In this paper, there made a brief introduction of the significance of image encryption technology and the status quo, and summed up the encryption algorithm of the existing image and analyzed there strengths and weaknesses, and introduced the wavelet analysis theory and chaos theory and its advantages in particularly. As if the image is transformed by wavelet, the wavelet transform coefficient if there is a change, will be adopted by the inverse computing of wavelet transform embodied in all the pixels, the encrypted outcome will be much better. At the same time, in virtue of chaotic system has pseudo-random and sensitive characteristic to the initial value and parameters, so that it is applied in the wide range of image encryption. Therefore, this paper introduces chaos mapping to design an encryption algorithm, which is based on wavelet transform two-dimensional images of chaotic sequence. It presents a project of frequency coefficient matrix scrambling transformation and designed two transformations of pixels values substitute in the algorithm. The Scrambling and pixel values substitute transformation are controlled by a variety of Chaos sequences, which solved single chaotic encryption system insecurity. The simulation experiments and theoretical analysis to prove that the method has a good effect and higher encryption security to meet the requirements of image encryption.