Cryptanalysis of an MPEG-Video Encryption Scheme Based on Secret Huffman Tables

This paper studies the security of a recently-proposed MPEG-video encryption scheme based on secret Huffman tables. Our cryptanalysis shows that: 1) the key space of the encryption scheme is not sufficiently large against divide-and-conquer (DAC) attack and known-plaintext attack; 2) it is possible to decrypt a cipher-video with a partially-known key, thus dramatically reducing the complexity of the DAC brute-force attack in some cases; 3) its security against the chosen-plaintext attack is very weak. Some experimental results are included to support the cryptanalytic results with a brief discuss on how to improve this MPEG-video encryption scheme.Comment: 8 pages, 4 figure

A New Cryptographic Strategy for Digital Images

In this paper, a new image block cipher encryption strategy for gray scale images using a different set of secret key and sizes is proposed. Initially, the swapping and dispersion is done without keys and in second stage the image is mixed with the chirikov map involving first secret key.  'N' rounds are taken to complete this process. The blended image is divided into blocks of block size 8X8.These blocks are also swapped to achieve good confusion. For making the encryption scheme more sturdy in each block the transmutation of pixels is done with the modified logistic map having three more secret keys.  The proposed scheme is simple, rapid and sensitive to the secret key. Due to the high order of substitution, common attacks such as linear and differential cryptanalysis are unattainable. The experimental results show that the proposed encryption technique is effective and has high security features.DOI:http://dx.doi.org/10.11591/ijece.v4i3.632

Improved method for image security based on chaotic-shuffle and chaotic-diffusion algorithms

In this paper, we propose to enhance the security performance of the color image encryption algorithm which depends on multi-chaotic systems. The current cryptosystem utilized a pixel-chaotic-shuffle system to encode images, in which the time of shuffling is autonomous to the plain-image. Thus, it neglects to the picked plaintext and known-plaintext attacks. Also, the statistical features of the cryptosystem are not up to the standard. Along these lines, the security changes are encircled to make the above attacks infeasible and upgrade the statistical features also. It is accomplished by altering the pixel-chaotic-shuffle component and including another pixel-chaotic-diffusion system to it. The keys for diffusion of pixels are extracted from the same chaotic arrangements created in the past stage. The renovation investigations and studies are performed to exhibit that the refreshed version of cryptosystem has better statistical features and invulnerable to the picked plaintext and known plaintext attacks than the current algorithm