Images Encryption Method using Steganographic LSB Method, AES and RSA algorithm

Abstract

Vulnerability of communication of digital images is an extremely important issue nowadays, particularly when the images are communicated through insecure channels. To improve communication security, many cryptosystems have been presented in the image encryption literature. This paper proposes a novel image encryption technique based on an algorithm that is faster than current methods. The proposed algorithm eliminates the step in which the secrete key is shared during the encryption process. It is formulated based on the symmetric encryption, asymmetric encryption and steganography theories. The image is encrypted using a symmetric algorithm, then, the secret key is encrypted by means of an asymmetrical algorithm and it is hidden in the ciphered image using a least significant bits steganographic scheme. The analysis results show that while enjoying the faster computation, our method performs close to optimal in terms of accuracy.

Medical and Biological Image Analysis

“…Graph colouring problem steganography and watermarking can also be a solution to increase safety [12,24]. Steganography is a technique used to hide secret data in media imperceptibly (Figure 11).…”

“…The correlation coefficient (CC) determines the relationship and degree of similarity between two variables. In a cryptosystem of images, the correlation is used to measure the difference between two images [4,12], the relationship between the pixels at the same location in the Medical and Biological Image Analysis manifest image and the ciphered image. The correlation is a useful measure for judging the quality of the cryptosystem [12,13].…”

“…The intermittent deviation (ID) indicates the divergence that has the pixel of the original image [12]. If the irregular deviation is close to a distribution uniform, so this is a good parameter of resistance against statistic attacks [4].…”

“…If the decrypted image is very similar to the original image, then the encryption system is resistant to noise. To measure the noise, we compare the peak signal-to-noise ratio (PSNR) of the original image and the encrypted image, the PSNR is given by the formula [12]:…”

Medical and Biological Image Analysis

“…For a robust cryptosystem, the correlation coefficient (CC) must be very close to zero. Thus, the success of the encryption process signifies small values of CC, and the encrypted image is random and highly uncorrelated [12]. It guarantees that the algorithm is resistant to pixel correlation attack.…”