An image encryption scheme based on three-dimensional Brownian motion and chaotic system

At present, many chaos-based image encryption algorithms have proved to be unsafe, few encryption schemes permute the plain images as three-dimensional(3D) bit matrices, and thus bits cannot move to any position, the movement range of bits are limited, and based on them, in this paper we present a novel image encryption algorithm based on 3D Brownian motion and chaotic systems. The architecture of confusion and diffusion is adopted. Firstly, the plain image is converted into a 3D bit matrix and split into sub blocks. Secondly, block confusion based on 3D Brownian motion(BCB3DBM)is proposed to permute the position of the bits within the sub blocks, and the direction of particle movement is generated by logistic-tent system(LTS). Furthermore, block confusion based on position sequence group(BCBPSG) is introduced, a four-order memristive chaotic system is utilized to give random chaotic sequences, and the chaotic sequences are sorted and a position sequence group is chosen based on the plain image, then the sub blocks are confused. The proposed confusion strategy can change the positions of the bits and modify their weights, and effectively improve the statistical performance of the algorithm. Finally, a pixel level confusion is employed to enhance the encryption effect. The initial values and parameters of chaotic systems are produced by the SHA 256 hash function of the plain image. Simulation results and security analyses illustrate that our algorithm has excellent encryption performance in terms of security and speed.     

红外和可见光图像高效融合的人工智能技术研究

为提升红外和可见光图像融合后图像的清晰度和细节信息的丰富程度,提出了基于人工智能技术的红外和可见光图像融合方法.通过NSCT变换分别将红外图像和可见光图像分解成低频低通子带和高频带通子带两个部分,采用低频系数加权平均求均值的选择方法、系数值选大法与局部区域融合规则相结合的方法,完成低频低通子带的图像和高频带通子带图像的...     

一种简洁的离散快速无振荡跟踪-微分器的设计

针对几种传统的跟踪-微分器存在的缺点,构造了一种简洁的离散快速无振荡跟踪-微分器.对几种跟踪-微分器的控制综合函数进行了对比分析,设计了一种可变宽度线性区,利用状态倒推的方法确定了控制综合函数,并依此构造跟踪-微分器.仿真结果表明,该跟踪-微分器能够快速无振荡地跟踪输入信号,具有较好地滤波功能,能输出品质很好的微分信号...     

系统单芯片之外的另一种选择——SOP

当今主流半导体有些技术上的限制,系统单芯片的设计并不适用于所有的系统,为了要达到高度集成的目的,同时保持系统应有的效能及可接受的成本,System-on-Package(SOP)被提出来,成为系统单芯片之外的另一种选择.本文将简介SOP的背景、技术,且分析SOP与其它集成技术的异同,及其发展概况.     

级联环腔增益箝制掺铒光纤放大器中的拍频现象及其抑制

利用简化的Giles模型在理论上得到了级联环腔箝制掺铒光纤放大器 (EDFA)中在信道数目发生变化时可能发生的剩余信道功率的拍频现象的解释和一般规律 ,并通过数值模拟和实验验证了这一结果。考虑到其对在网络管理方案中广泛采用的调顶技术下可能对系统误码有较大的影响 ,给出了避免这一现象发生的方法     

新型非易失性存储器

 存储器是计算机系统的重要组成部分。按照在存储体系中的位置不同,存储器可以简单地分为片上内存、主存和硬盘三种类型。与此相对应,静态存储器(SRAM)、动态存储器(DRAM)和磁盘各自成为实现这三种主要存储类型的传统技术。在过去的近40年里,这三种技术取得了巨大的技术和商业成就。除磁盘外,静态存储器和动态存储器的制造都依赖于半导体集成技术。     

A novel color image encryption algorithm based on genetic recombination and the four-dimensional memristive hyperchaotic system

Recently, many image encryption algorithms based on chaos have been proposed. Most of the previous algorithms encrypt components R, G, and B of color images independently and neglect the high correlation between them. In the paper, a novel color image encryption algorithm is introduced. The 24 bit planes of components R, G, and B of the color plain image are obtained and recombined into 4 compound bit planes, and this can make the three components affect each other. A four-dimensional(4D) memristive hyperchaotic system generates the pseudorandom key streams and its initial values come from the SHA 256 hash value of the color plain image. The compound bit planes and key streams are confused according to the principles of genetic recombination, then confusion and diffusion as a union are applied to the bit planes,and the color cipher image is obtained. Experimental results and security analyses demonstrate that the proposed algorithm is secure and effective so that it may be adopted for secure communication.