Intersecured joint image compression with encryption purpose based on fractal mating coding

Abstract

In this study, a pioneer secure coding concept for pairwise images is revealed and implemented by the use of the proposed fractal mating coding scheme, in which the domain pools consist of the domain blocks selected from the pairwise images to explore both the intra-and inter-image similarities. In addition to the pairwise relation, the mating ratios denoting the percentages of the domain blocks selected from both images are utilized. Further encryption can be achieved by the use of block mean permutation and mating of the fractal codes. The security level is high because that the jointly coded images cannot be correctly reconstructed without all the required information. The computer experiments show that the coding performance can be greatly improved from conventional fractal coding schemes and the inter-secured purpose for pairwise images is successfully achieved.

Image encoding based on a damped triangular function and a discrete sequence

“…Thus, the encoding has been completed and the result is shown in Figure 5(b). To determine the encoding quality, H, r and PSNR are computed via Equations (5), (6) and (8), respectively. The results are H ¼ 4.166, r ¼ 0.064 and PSNR ¼ 5.265.…”

“…The baboon decoding is shown in Figure 6(b) and the pepper decoding is shown in Figure 6(c). The decoding quality is determined by computing the parameters r and PSNR via Equations (6) and (8), respectively. These parameters are calculated by using the original image and the decoded image of Lenna, baboon, peppers and harness.…”

“…Image encoding is a powerful tool to protect image data that are transmitted electronically [1][2][3][4][5][6][7][8]. Thus, the original image is transmitted as a secret image and it is decoded by an authorised receiver.…”

“…Then, the maps are converted into bytes to obtain the secret image. The fractal method generates the secrete image by mapping the original image into blocks based on an affine transformation [5,6]. This method computes the decoding based on a pair-wise relationship between two encoded images.…”