Abstract: Secured image compression is the key issue in image transmission applications. This paper proposes the idea of combining both compression and security of an image. In the existing methods to encrypt images, the key size is too large since the whole matrix is considered as the key. To solve this problem, encryption through key controlled matrix is constructed using the logistic map in this proposed method. Then Arnold transform is used for image location scrambling. First the input image is decomposed into bands and compressed by level dependent hard threshold method and then combined with above encryption algorithms to get compressed-encrypted image. This algorithm produces a cipher for test images that have good diffusion and confusion properties. Simulation results of histogram analysis, key sensitivity analysis of adjacent pixels and PSNR shows the enhanced security and effectiveness of the proposed algorithm and reasonable increase in compression performance.

Keywords: Arnold transforms chaos system, encryption, and Image compression.