An Efficient Image Cryptographic Algorithm based on Frequency Domain using Haar Wavelet Transform

Abstract

Presently a number of techniques are used to restrict confidential image data from unauthorized access. In this paper, the authors have proposed an efficient lossless image cryptographic algorithm to transmit pictorial data securely. Initially we take a 64 bit key, we convert our decimal pixel value into binary 8 bits and we XOR the first 8 bits of the key with the pixel value. After that we take the next 8 bits of the key and XOR with the next pixel value. We perform the circular right shit operation when the key gets exhausted. We perform the first level haar wavelet decomposition thereafter. Dividing the LL1 into four equal sections we perform some swapping operations. Decryption follows the reverse of the encryption .Evaluation is done by some parametric tests which includes correlation analysis, NPCR, UACI readings etc. show that the proposed work is resilient and robust in the field of cryptography.