In traditional chaotic map based image encryption algorithm, the encryption performance is determined by the permutation generating speed, and due to short periodical problem led by the finite precision effect, the pe...
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ISBN:
(纸本)9783642319181;9783642319198
In traditional chaotic map based image encryption algorithm, the encryption performance is determined by the permutation generating speed, and due to short periodical problem led by the finite precision effect, the permutation generating is always in a low efficient. In this paper, a method to generate a large permutation by combining several small permutation arrays is proposed by introducing a join operation to improve the permutation generating speed, where small permutation arrays are generated by one-dimensional chaotic map. Based on this permutation generating, an image encryption algorithm is proposed where XOR and MOD based diffusion procedures are added. The complete image encryption algorithm is a multiple rounds of substitution-permutation network where permutation and diffusion as the basic building blocks. Experiments show that the proposed algorithm is a key-sensitive, can resist different attacks such as differential attack and plaintext attack, and the ciphered image is similar to a noise image.
We develop a connection between permutation arrays that are used in powerline communication and well-studied combinatorial objects, mutually orthogonal latin squares (MOLS). From this connection, many new results on p...
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We develop a connection between permutation arrays that are used in powerline communication and well-studied combinatorial objects, mutually orthogonal latin squares (MOLS). From this connection, many new results on permutation arrays can be obtained.
An (n, d, k)-mapping f is a mapping from binary vectors of length n to permutations of length n + k such that for all x, y is an element of {0, 1}(n), d(H) (f (x), f (y)) >= d(H)(x, y) + d, if d(H) (x, y) (n + k)-...
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An (n, d, k)-mapping f is a mapping from binary vectors of length n to permutations of length n + k such that for all x, y is an element of {0, 1}(n), d(H) (f (x), f (y)) >= d(H)(x, y) + d, if d(H) (x, y) <= (n + k)-d and d(H) (f (x), f (y)) = n + k, if d(H) (x, y) > (n + k)-d. In this paper, we construct an (n, 3, 2)-mapping for any positive integer n >= 6. An (n, r)-permutation array is a permutation array of length n and any two permutations of which have Hamming distance at least r. Let P (n, r) denote the maximum size of an (n, r)-permutation array and A (n, r) denote the same setting for binary codes. Applying (n, 3, 2)-mappings to the design of permutation array, we can construct an efficient permutation array (easy to encode and decode) with better code rate than previous results [Chang (2005). IEEE Trans inf theory 51:359-365, Chang et al. (2003). IEEE Trans Inf Theory 49:1054-1059;Huang et al. (submitted)]. More precisely, we obtain that, for n >= 8, P(n, r) >= A(n-2, r-3) > A(n-1, r-2) = A (n, r-1) when n is even and P(n, r) >= A(n-2, r-3) = A(n-1, r-2) > A(n, r-1) when n is odd. This improves the best bound A(n-1, r-2) so far [Huang et al. (submitted)] for n >= 8.
Let PA(n, d) be a permutation array (PA) of order n and the minimum distance d. We propose a new construction of the permutation array PA (pm, p(m-1) k) for a given prime number p, a positive integer k = 2p/3. Moreove...
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Let PA(n, d) be a permutation array (PA) of order n and the minimum distance d. We propose a new construction of the permutation array PA (pm, p(m-1) k) for a given prime number p, a positive integer k < p and a positive integer m. The resulted array has (vertical bar PA(p, k) . p((m-1)(p-k)))(m) rows. Compared to the other constructions, the new construction gives a permutation array of far bigger size with a large minimum distance, for example, when k >= 2p/3. Moreover the proposed construction provides an algorithm to find the i-th row of PA (p(m), p(m-1) k) for a given index i very simply.
We give an explicit decoding scheme for the permutation arrays under Hamming distance metric, where the encoding is constructed via a distance-preserving mapping from ternary vectors to permutations (3-DPM).
We give an explicit decoding scheme for the permutation arrays under Hamming distance metric, where the encoding is constructed via a distance-preserving mapping from ternary vectors to permutations (3-DPM).
We study a decomposition of Fl(n)(d-1), where: Fl(n) denotes the flag manifold over C-n. The strata are defined by the dimensions of intersections of one space from each fag, so for d equal to 2 this is the usual Bruh...
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We study a decomposition of Fl(n)(d-1), where: Fl(n) denotes the flag manifold over C-n. The strata are defined by the dimensions of intersections of one space from each fag, so for d equal to 2 this is the usual Bruhat cell decomposition, The strata are indexed by "permutation arrays," which are d-dimensional analogs of permutation matrices. We present a partial order on these permutation arrays, specializing: to the Bruhat order on S-n when d equals 2 and to the lattice of partitions of a d-set when n equals 2. (C) 2000 Academic Press.
We survey a number of topics and constructions of combinatorial arrays based on finite fields. These combinatorial objects include orthogonal arrays, covering arrays, ordered orthogonal arrays, permutation arrays, fre...
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We survey a number of topics and constructions of combinatorial arrays based on finite fields. These combinatorial objects include orthogonal arrays, covering arrays, ordered orthogonal arrays, permutation arrays, frequency permutation arrays, hypercubes and Costas arrays.
In this paper we prove new lower bounds for the maximal size of permutation codes by connecting the theory of permutation codes with the theory of linear block codes. More specifically, using the columns of a parity c...
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In this paper we prove new lower bounds for the maximal size of permutation codes by connecting the theory of permutation codes with the theory of linear block codes. More specifically, using the columns of a parity check matrix of an [n,k,d](q) linear block code, we are able to prove the existence of a permutation code in the symmetric group of degree n, having minimum distance at least d and large cardinality. With our technique, we obtain new lower bounds for permutation codes that enhance the ones in the literature and provide asymptotic improvements in certain regimes of length and distance of the permutation code.
A permutation code of length n and distance d is a set I" of permutations from some fixed set of n symbols such that the Hamming distance between each distinct x,yaI" is at least d. In this note, we determin...
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A permutation code of length n and distance d is a set I" of permutations from some fixed set of n symbols such that the Hamming distance between each distinct x,yaI" is at least d. In this note, we determine some new results on the maximum size of a permutation code with distance equal to 4, the smallest interesting value. The upper bound is improved for almost all n via an optimization problem on Young diagrams. A new recursive construction improves known lower bounds for small values of n.
This paper focuses on correcting a theorem relating to the construction of permutation group codes (PGCs). The theorem in question assumed that affine transformation could be used to enumerate all the code words of a ...
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This paper focuses on correcting a theorem relating to the construction of permutation group codes (PGCs). The theorem in question assumed that affine transformation could be used to enumerate all the code words of a permutation array with a minimum Hamming distance (MHD) of n 1 for any n > 1. This assumption was founded upon the proposition that, if the code length, n, is a prime power, then the maximum cardinality of the code will be n(n - 1) and its MHD will be n - 1. However, two typical algebraic methods, one relying on affine transformation and another upon the composite operation of two small subgroups of a symmetric group, can violate this proposition. This is because it is only when n is a prime rather than a prime power that they can enumerate all the code words of an (nI n(n - 1);n - 1)-PGC. By investigating how the range of n impacts upon the cardinality and MHD of a code, we provide a corrective theorem that stipulates the construction of (p(q);p(2q)(1 - 1/p);p(q)(1- 1/p))-PGCs when n = p(q) is a prime power, where p is a prime and q > 1. On the basis of this theorem, and under the condition of n being the power of 2, we construct a (2(q);2(2q-1);2(q-1))-PGC and present an encoder that can map a k-bit binary information sequence to an n D 22q-dimension permutation code word. The natural array structure of 2(q);2(2q-1);2(q-1))-PGCs makes them especially well-suited to forming the basis of low-complexity encoders. We present simulation-based experiments that show that, as the code length increases, the performance of these codes improves. The best performance is for a (16;128;8)-PGC, which can achieve -3.8 dB with a word error rate of 10(-7).
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