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一种新颖的水印方法——Wavelet过滤器参数方法

1概要本文提出了使用Wavelet过滤器参数作为提高许多算法的安全性的一种手段,并且依靠Wavelet过滤器的密钥方法很容易成为一种安全框架。另外,还提供了一种新颖的水印技术,能适合独立的新图像码标准的码组进程方法。两种应用脚本,版权保护和图像真实性是能够被认可的,基于质量的嵌入技术能成功地在高速运转的JPEG2000进程中加密和解密一个二进制水印。在水印应用中,水印的检测、抽取、修改和删除都会带来安全问题并且能容忍恶意的攻击。水印攻击是攻击水印图像或攻击潜在的协议层,其目的是破坏水印应用的目标。所有对水印图像的扭曲都被认为是一种攻击。因此,我们要区分有意或敌对的攻击和无意的攻击。敌对水印攻击的唯一目的是破坏水印,而无意攻击在正常的图像操作中经常发生,例如压缩。我们同时也要区分水印的健壮性问题和安全性问题。健壮性是容忍图像扭曲的一种水印技术的财富。理想的状态是对用作版权保护的水印技术应能正确地抽取或检测水印,只要主机的图像仍然有...  (本文共4页) 阅读全文>>

《Science in China,Ser.A》2005年05期
Science in China,Ser.A

Tree wavelet approximations with applications

1 IntrodUCtion The first Purpose of this PaPer 15 to Present and analyze a eonstrUetive greedy scheme (CGS)which generates a Part】tion of an invariant set aeeording to a given funetion.The Partition 15 then used to eonstrUet a Piecewise Polyno而al aPProximation to the giVen func- tion.OPtimal order of eonvergenee 15 obtained for several norms including the Sobolev and Besov norms.The estimation of the oPtimal eonverge...  (本文共23页) 阅读全文>>

《Journal of Southwest Jiaotong University》2005年01期
Journal of Southwest Jiaotong University

Novel Adaptive Beamforming Algorithm Based on Wavelet Packet Transform

IntroductionAdaptivebeamformingtechniqueisusedwidelyinaeronautics, astronautics, radarandcommunicationsystems. Abeamformerisaspatialfilterthatoperatesontheoutputofanarrayofsensorsinordertoenhancetheamplitudeofacoherentwavefrontrelativetobackgroundnoiseanddirectionalinterference[1].LeastMeanSquare(LMS)adaptivebeamformingisasimpleandpracticalbeamformingtechnique. LMSalgorithmhasmanyadvantages, suchaslowcom plexity, sim...  (本文共7页) 阅读全文>>

《Journal of Harbin Institute of Technology》2005年05期
Journal of Harbin Institute of Technology

Application of wavelet transform to recursive prediction of vibration signals

Much attention has been given to time series pre-diction in many fields, such as fault diagnosis[1],weather forecast, oil exploration, electric power distri-bution, satellite communication etc. However, mostprediction methods use a linear model to represent thepredicted object in a stationary time series, such as theAR and ARMA model prediction. Because the sam-pling data can be affected by many practical measure-men...  (本文共6页) 阅读全文>>

《Chinese Science Bulletin》2005年16期
Chinese Science Bulletin

Complete quantum circuit of Haar wavelet based MRA

Quantum computation is a new interdisciplinary field of research in the intersection of computer science, phys- ics and mathematics. Deutsch first proposed the universal quantum Turing machine model and devised the earliest quantum algorithms[1,2]. And he also extended the theory of quantum computation with quantum computational networks[3]. But it was Shor’s discrete logarithms and factoring algorithms[4,5], which w...  (本文共3页) 阅读全文>>

《Journal of Systems Engineering and Electronics》2005年04期
Journal of Systems Engineering and Electronics

Multisensor image fusion algorithm using nonseparable wavelet frame transform

1.INTRODUCTION Withtherapidimprovementofsensortechnology,numerousmultisensordata,whichoftencontaincom plementaryandredundantinformationaboutthere gionsurveyed,areobtainedinmanyfieldssuchasre motesensing,medicalimaging,machinevisionand militaryapplications.Sensorfusionisincreasinglybe comingapromisingresearcharea.Itcanbedivided intosignal,pixel,feature,andsymbollevels.The papermainlyaddressestheproblemofpixellevelim a...  (本文共5页) 阅读全文>>