Multistage Compression of Encrypted Images for Band Effective Secured Transmission and Reconstruction
D. Venugopal, Anita Raja, Maheshwar Rao K. Uma · International journal of tomography and simulation · 2013
This work proposes a novel scheme for compression and proper reconstruction of encrypted images with optimum compression ratio and PSNR. When it is desired to transmit redundant data of image over an insecure and bandwidth- constrained channel, it is customary to first compress the image and then encrypt it. In this paper, we investigate the novelty of reversing the order of these steps as first encrypting and then compressing by proper tradeoff between compression efficiency and information security. An original image is encrypted by adding a cryptographic key for providing privacy and secrecy between the sender and receiver. Then the encrypted image is compressed in multistage, here it is two times compressed by the coefficients that are generated from Haar wavelet transform. After receiving the compressed image with the help of secret key, a receiver can reconstruct the principal content of the original image by the inverse Haar wavelet transform.