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Malicious Code Modeling and Analysis in Weighted Scale-Free Networks 被引量:2
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作者 WANG Changguang WANG Fangwei +1 位作者 ZHANG Yangkai MA Jianfengi 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期51-54,共4页
We study the detailed malicious code propagating process in scale-free networks with link weights that denotes traffic between two nodes. It is found that the propagating velocity reaches a peak rapidly then decays in... We study the detailed malicious code propagating process in scale-free networks with link weights that denotes traffic between two nodes. It is found that the propagating velocity reaches a peak rapidly then decays in a power-law form, which is different from the well-known result in unweighted network case. Simulation results show that the nodes with larger strength are preferential to be infected, but the hierarchical dynamics are not clearly found. The simulation results also show that larger dispersion of weight of networks leads to slower propagating, which indicates that malicious code propagates more quickly in unweighted scale-free networks than in weighted scale-free networks under the same condition. These results show that not only the topology of networks but also the link weights affect the malicious propagating process. 展开更多
关键词 malicious code weighted scale-free networks propagation model
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A Weight-Coded Evolutionary Algorithm for the Multidimensional Knapsack Problem 被引量:2
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作者 Quan Yuan Zhixin Yang 《Advances in Pure Mathematics》 2016年第10期659-675,共17页
A revised weight-coded evolutionary algorithm (RWCEA) is proposed for solving multidimensional knapsack problems. This RWCEA uses a new decoding method and incorporates a heuristic method in initialization. Computatio... A revised weight-coded evolutionary algorithm (RWCEA) is proposed for solving multidimensional knapsack problems. This RWCEA uses a new decoding method and incorporates a heuristic method in initialization. Computational results show that the RWCEA performs better than a weight-coded evolutionary algorithm pro-posed by Raidl (1999) and to some existing benchmarks, it can yield better results than the ones reported in the OR-library. 展开更多
关键词 weight-Coding Evolutionary Algorithm Multidimensional Knapsack Problem (MKP)
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Study on cipher propertys of constant weight codes
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作者 Lin Bogang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期458-461,共4页
Constant weight code is an important error-correcting control code in communications. Basic structure of constant weight codes for some arriving at Johnson bound, A(n, 2u, w), is presented. Some correlative property... Constant weight code is an important error-correcting control code in communications. Basic structure of constant weight codes for some arriving at Johnson bound, A(n, 2u, w), is presented. Some correlative propertys of the codes, the solution of arriving at Johnson bound, and the results on the couple constant code and some constant weight codes are discussed. The conclusion is verified through four examples. 展开更多
关键词 constant weight code Johnson bound couple relation boundary property combination cipher.
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Linear Codes with Two Weights or Three Weights from Two Types of Quadratic forms
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作者 Zhu Xiaoxing Xu Dazhuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第1期62-71,共10页
Let F_qbe afinite field with q=pmelements,where pis an odd prime and mis apositive integer.Here,let D_0={(x_1,x_2)∈F_q^2\{(0,0)}:Tr(x_1^(pk1+1)+x_2^(pk2+1))=c},where c∈F_q,Tr is the trace function fromFF_qtoFpand m/... Let F_qbe afinite field with q=pmelements,where pis an odd prime and mis apositive integer.Here,let D_0={(x_1,x_2)∈F_q^2\{(0,0)}:Tr(x_1^(pk1+1)+x_2^(pk2+1))=c},where c∈F_q,Tr is the trace function fromFF_qtoFpand m/(m,k_1)is odd,m/(m,k_2)is even.Define ap-ary linear code C_D =c(a_1,a_2):(a_1,a_2)∈F_q^2},where c(a_1,a_2)=(Tr(a_1x_1+a_2x_2))_((x1,x2)∈D).At most three-weight distributions of two classes of linear codes are settled. 展开更多
关键词 linear codeS weight distribution GAUSS SUM WEIL SUM
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Lexicographic Constant-Weight Equidistant Codes over the Alphabet of Three, Four and Five Elements
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作者 Todor Todorov Galina Bogdanova Teodora Yorgova 《Intelligent Information Management》 2010年第3期183-187,共5页
In this paper we consider the problem of finding bounds on the size of lexicographic constant-weight equidistant codes over the alphabet of three, four and five elements with 2 ≤ w 【n ≤ 10. Computer search of lexic... In this paper we consider the problem of finding bounds on the size of lexicographic constant-weight equidistant codes over the alphabet of three, four and five elements with 2 ≤ w 【n ≤ 10. Computer search of lexicographic constant-weight equidistant codes is performed. Tables with bounds on the size of lexicographic constant-weight equidistant codes are presented. 展开更多
关键词 LEXICOGRAPHIC codeS Equidistant codeS Constant-weight codeS BOUNDS of codeS
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Construction and Weight Distributions of Binary Linear Codes Based on Deep Holes
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作者 Yong Yang Wenwei Qiu 《Applied Mathematics》 2023年第10期684-695,共12页
Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, ... Deep holes are very important in the decoding of generalized RS codes, and deep holes of RS codes have been widely studied, but there are few works on constructing general linear codes based on deep holes. Therefore, we consider constructing binary linear codes by combining deep holes with binary BCH codes. In this article, we consider the 2-error-correcting binary primitive BCH codes and the extended codes to construct new binary linear codes by combining them with deep holes, respectively. Furthermore, three classes of binary linear codes are constructed, and then we determine the parameters and the weight distributions of these new binary linear codes. 展开更多
关键词 Linear codes MacWilliams Equations weight Distribution Dual codes Deep Holes Covering Radius
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Hybrid weighted symbol-flipping decoding for nonbinary LDPC codes
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作者 刘冰 Tao Wei +1 位作者 Dou Gaoqi Gao Jun 《High Technology Letters》 EI CAS 2013年第1期58-62,共5页
A hybrid decoding algorithm is proposed for nonbinary low-density parity-check (LDPC) codes, which combines the weighted symbol-flipping (WSF) algorithm with the fast Fourier trans- form q-ary sum-product algorit... A hybrid decoding algorithm is proposed for nonbinary low-density parity-check (LDPC) codes, which combines the weighted symbol-flipping (WSF) algorithm with the fast Fourier trans- form q-ary sum-product algorithm (FFT-QSPA). The flipped position and value are determined by the symbol flipping metric and the received bit values in the first stage WSF algorithm. If the low- eomplexity WSF algorithm is failed, the second stage FFT-QSPA is activated as a switching strategy. Simulation results show that the proposed hybrid algorithm greatly reduces the computational complexity with the performance close to that of FFT-QSPA. 展开更多
关键词 nonbinary low-density (WSF) hybrid weighted symbol-flipping parity-check (LDPC) code (HWSF) iterative decoding weighted symbol-flipping
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Theoretical Analysis of Bit-Error Probability for Convolutional Codes with Weight Enumerators
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作者 Zhang Tianyi 《无线互联科技》 2012年第12期123-125,共3页
The paper introduces the state reduction algorithm and accelerated state reduction algorithm are used to compute the distance weight enumerator(transfer function)T[x,y] of convolutional codes.Next use computer simulat... The paper introduces the state reduction algorithm and accelerated state reduction algorithm are used to compute the distance weight enumerator(transfer function)T[x,y] of convolutional codes.Next use computer simulation to compare upper bound on the bit error probability on an additive white Gaussian noise(AWGN) for maximum free distance(MFD) codes of previously found and optimum distance spectrum(ODS) codes with rate 1/4,overall constraint length are 5 and 7,respectively.Finally,a method of how to search for good convolutional codes is given. 展开更多
关键词 英文摘要 编辑工作 学术论文 期刊
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Error Probability for Convolutional Codes with Weight Enumerating Function
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作者 Tianyi Zhang Yongtao Liu 《无线互联科技》 2013年第1期121-122,共2页
The paper introduces the state reduction algorithm and accelerated state reduction algorithm are used to compute the distance weight enumerator(transfer function) T[x,y] of convolutional codes.Next use computer simula... The paper introduces the state reduction algorithm and accelerated state reduction algorithm are used to compute the distance weight enumerator(transfer function) T[x,y] of convolutional codes.Next use computer simulation to compare upper bound on the bit error probability on an additive white Gaussian noise (AWGN) for maximum free distance (MFD) codes of previously found and optimum distance spectrum (ODS) codes with rate 1/4,overall constraint length are 5 and 7,respectively. Finally,a method of how to search for good convolutional codes is given. 展开更多
关键词 无线技术 互联网 无线网络 网络科技
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基于静态分析的代码规范评价最优化策略研究
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作者 曹炳尧 刘玉婷 《工业控制计算机》 2026年第2期73-74,156,共3页
针对当前代码规范性检测方法中存在的检测目标单一及缺少量化评分等问题,提出一种基于静态分析的代码规范性评价最优化策略。通过静态分析技术提取代码特征并进行规范匹配,检测并反馈代码在六大维度上的规范性缺陷。采用熵权法计算六大... 针对当前代码规范性检测方法中存在的检测目标单一及缺少量化评分等问题,提出一种基于静态分析的代码规范性评价最优化策略。通过静态分析技术提取代码特征并进行规范匹配,检测并反馈代码在六大维度上的规范性缺陷。采用熵权法计算六大维度的客观权重,结合拉格朗日乘子法融合客观权重与教师主观权重以计算评分。实验结果表明,该方法能成功检测所有定义的缺陷且在评分准确率上优于既有方法。 展开更多
关键词 代码规范 代码评分 代码静态分析 拉格朗日乘子法 熵权法
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误码条件下基于码字特征的一种TPC码盲识别算法
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作者 曾翔宇 石雨桐 +1 位作者 刘林 马征 《电子信息对抗技术》 2026年第1期43-54,共12页
信道编码盲识别是通信对抗领域的热点研究方向。目前Turbo乘积码(Turbo Product Codes,TPC)盲识别技术仅可识别单一子码类型下的子码码长,而无法识别多种子码类型及子码码长,不足以支撑实际需求。因此,通过对TPC码的子码及其结构、编码... 信道编码盲识别是通信对抗领域的热点研究方向。目前Turbo乘积码(Turbo Product Codes,TPC)盲识别技术仅可识别单一子码类型下的子码码长,而无法识别多种子码类型及子码码长,不足以支撑实际需求。因此,通过对TPC码的子码及其结构、编码方式等进行研究和分析,探明了不同子码类型码字特点。研究表明,子码为扩展BCH(Bose-Chaudhuri-Hocquenghem)码的TPC码,子码码重均为偶数,且二维TPC码和三维TPC码均满足该特性。子码为本原BCH码的TPC码,其最短子码码长满足特定的约束关系:二维TPC码其较短的子码码长是满足平方小于TPC码长且符合BCH码长特征的最大数。子码为缩短BCH码的TPC码,子码码重与码长无明显规律,但是其子码生成多项式和相应的本原生成多项式相同,通过遍历生成多项式可以得到正确的子码码长。基于以上码字特征,提出了基于码重奇偶性等多维特性的通用TPC码子码类型及参数盲识别算法。仿真结果表明,在误码率为1×10^(-3)的情况下,可以有效的识别出各种TPC码的子码类型以及子码码长。 展开更多
关键词 信道编码 TPC码 BCH码 盲识别 码重
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一类线性码及其子域码
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作者 柴烨 朱士信 开晓山 《电子与信息学报》 北大核心 2026年第1期222-229,共8页
少重量线性码在秘密共享、强正则图、关联方案和认证码等方面有着广泛的应用。该文基于有限域上Kloosterman和,完全确定了一类q元少重量线性码及其删余码的参数和重量分布,研究了它们的对偶码及其子域码,得到了关于球包界最优的线性码。
关键词 重量分布 子域码 删余码 Kloosterman
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多矩阵的代表性顺序统计量译码算法
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作者 王义文 王千帆 +2 位作者 梁济凡 宋林琦 马啸 《电子与信息学报》 北大核心 2026年第1期45-56,共12页
代表性顺序统计量译码(Representative Ordered Statistics Decoding,ROSD)是一类针对阶梯矩阵码提出的能够支持并行高斯消元(Gaussian Elimination,GE)的高效译码算法。该文将ROSD推广至一般线性分组码,并利用最小重量阶梯生成矩阵(Min... 代表性顺序统计量译码(Representative Ordered Statistics Decoding,ROSD)是一类针对阶梯矩阵码提出的能够支持并行高斯消元(Gaussian Elimination,GE)的高效译码算法。该文将ROSD推广至一般线性分组码,并利用最小重量阶梯生成矩阵(Minimum-Weight Staircase Generator Matrix,MWSGM)构造方法,为任意线性分组码生成对应的阶梯矩阵结构。在此基础上,该文特别提出了基于MWSGM的多矩阵构造与选择策略。具体而言,构造阶段在第0行(第1个阶梯)分别保留前M个最小重量候选码字,并对每个给定的候选独立地搜索后续各行,最终得到M个不同的阶梯生成矩阵。该多矩阵构造方法放宽了重编码基的选择约束,从而提升了其质量。译码阶段则根据各阶梯矩阵对应的可选重编码基的可靠度总和来选择一个阶梯矩阵,并针对其执行ROSD算法。在性能分析方面,该文基于鞍点近似提出了帧错误率(Frame Error Rate,FER)的上界与平均搜索次数估计。数值结果显示:(1)所提基于鞍点的FER上界能够有效预测FER性能,且所提平均搜索次数估计与实际仿真结果较为吻合;(2)相比于原始单矩阵ROSD基线算法,所提基于MWSGM的多矩阵构造与选择策略在相同最大搜索次数约束下能够显著降低FER,并有效减少平均搜索次数。 展开更多
关键词 顺序统计量译码 多矩阵译码 并行高斯消元 阶梯矩阵码 最小重量阶梯生成矩阵
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几类MDS码和NMDS码的构造
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作者 杜小妮 薛婧 +1 位作者 乔兴斌 赵紫薇 《西北师范大学学报(自然科学版)》 2026年第1期41-48,共8页
MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为... MDS码是参数达到Singleton界的最优线性码,广泛应用于分布式存储系统和随机误差信道等领域.与之密切相关的NMDS码在保持近似纠错性能的同时,可以显著降低编译码复杂度,因此成为编码理论研究的热点之一.通过选取有限域F_(q^(2))(其中q为2的幂次)上单位圆盘中的元素来构造矩阵,并在其中添加一个列向量,将其作为生成矩阵构造了F_(q^(2))上几类码长为(q+2)的MDS码和NMDS码,研究了NMDS码的重量计数器;选取F_(q^(t))(t≥1为整数)中含有l(4<l≤q^(t))个元素的集合构造了码长为l的MDS码.研究发现,构造的MDS码均为Griesmer码,NMDS码均为near Griesmer码;码本表明,本文构造的所有码均为新码. 展开更多
关键词 MDS码 NMDS码 重量计数器 Griesmer界
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改进型Code-Matched交织器
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作者 罗骥 张曦林 袁东风 《山东大学学报(工学版)》 CAS 2005年第1期64-69,共6页
Turbo码作为信道编码方案 ,可以获得较高的误比特率 (BER)性能 ,而交织器的设计是影响Turbo码性能的关键环节 .笔者在码的重量分析的基础上提出了一种改进型Code Matched交织器 ,它可以减少低重量码的数量 ,从而提高Turbo码的性能 .这... Turbo码作为信道编码方案 ,可以获得较高的误比特率 (BER)性能 ,而交织器的设计是影响Turbo码性能的关键环节 .笔者在码的重量分析的基础上提出了一种改进型Code Matched交织器 ,它可以减少低重量码的数量 ,从而提高Turbo码的性能 .这种改进型Code Matched交织器可以适用于多种不同生成矩阵产生的Turbo码 ,而且不会影响Turbo码在中、高信噪比处的性能 ,同时 ,在Rayleigh信道下 。 展开更多
关键词 TURBO码 交织器 重量分布 code-Matched 距离谱
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GAUSS PERIODS AND CYCLIC CODES FROM CYCLOTOMIC SEQUENCES OF SMALL ORDERS 被引量:1
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作者 Hu Liqin Yue Qin Zhu Xiaomeng 《Journal of Electronics(China)》 2014年第6期537-546,共10页
Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, severa... Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, several cyclotomic sequences of order e =3, 4, 6 are employed to construct a number of classes of cyclic codes over GF(q) with prime length. Under certain conditions, the linear complexity and reciprocal minimal polynomials of cyclotomic sequences are calculated, and the lower bounds on the minimum distances of these cyclic codes are obtained. 展开更多
关键词 Sequence Cyclic code weight distribution Gauss period CYCLOTOMY
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Turbo Codes with Modified Code-matched Interleaver over A WGN and Rayleigh Fading Channel 被引量:1
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作者 罗骥 张曦林 袁东风 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2005年第2期147-152,共6页
A novel Code-Matched interleaver is proposed which decreases the number of the low weight codewords to improve the performance of the Turbo code. The modified design can adapt more kinds of Turbo codes determined by t... A novel Code-Matched interleaver is proposed which decreases the number of the low weight codewords to improve the performance of the Turbo code. The modified design can adapt more kinds of Turbo codes determined by the generator matrix, while it doesn't decrease the bit error rate performance of Turbo codes at moderate to high signal to noise ratio. At the same time, in Rayleigh fading channel, the new Code-Matched interleaver can also debase the error floor. 展开更多
关键词 TURBO INTERLEAVER weight distribution code-Matched distance spectrum
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Two Classes of Quaternary Codes from Z_4-valued Quadratic Forms
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作者 Zhu Xiaoxing Xu Dazhuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第5期896-912,共17页
Let R=GR (4,m)be a Galois ring with Teichmuller set T_m and Tr_m be the trace function fromRto Z_4.In this paper,two classes of quaternary codes C_1 = {c(a,b):a ∈R,b ∈ T_(m/2)},where c(a,b)=(Tr_m(ax)+Tr_(m/2)(2 bx^(... Let R=GR (4,m)be a Galois ring with Teichmuller set T_m and Tr_m be the trace function fromRto Z_4.In this paper,two classes of quaternary codes C_1 = {c(a,b):a ∈R,b ∈ T_(m/2)},where c(a,b)=(Tr_m(ax)+Tr_(m/2)(2 bx^(2 m/2 +1)))_(x∈T_m),and C_2= {c(a,b):a ∈ R,b ∈ T_m}, where c(a,b)=(Tr_m(ax+2 bx^(2 k+1)))_(x∈T_m),and m/gcd(m,k)is even,are investigated,respectively.The Lee weight distributions,Hamming weight distributions and complete weight distributions of the codes are completely given. 展开更多
关键词 GALOIS ring QUATERNARY code Hamming weight QUADRATIC form LEE weight
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A Depth Video Coding In-Loop Median Filter Based on Joint Weighted Sparse Representation
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作者 Lü Haitao YIN Cao +1 位作者 CUI Zongmin HU Jinhui 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第4期351-357,共7页
The existing depth video coding algorithms are generally based on in-loop depth filters, whose performance are unstable and easily affected by the outliers. In this paper, we design a joint weighted sparse representat... The existing depth video coding algorithms are generally based on in-loop depth filters, whose performance are unstable and easily affected by the outliers. In this paper, we design a joint weighted sparse representation-based median filter as the in-loop filter in depth video codec. It constructs depth candidate set which contains relevant neighboring depth pixel based on depth and intensity similarity weighted sparse coding, then the median operation is performed on this set to select a neighboring depth pixel as the result of the filtering. The experimental results indicate that the depth bitrate is reduced by about 9% compared with anchor method. It is confirmed that the proposed method is more effective in reducing the required depth bitrates for a given synthesis quality level. 展开更多
关键词 depth video coding virtual view synthesis joint weighted sparse representation
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The Digital Fingerprinting Method for Static Images Based on Weighted Hamming Metric and on Weighted Container Model
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作者 Sergey Bezzateev Natalia Voloshina 《Journal of Computer and Communications》 2014年第9期121-126,共6页
The algorithm of fingerprint constructing for still images based on weighted image structure model is proposed. The error correcting codes that are perfect in weighted Hamming metric are used as a base for fingerprint... The algorithm of fingerprint constructing for still images based on weighted image structure model is proposed. The error correcting codes that are perfect in weighted Hamming metric are used as a base for fingerprint constructing. 展开更多
关键词 Fingerprinting Error CORRECTING codeS Perfect codeS in weightED Hamming METRIC weightED Container Model Digital RIGHTS Management
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