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I摘要商品经济竞争激烈，假冒伪劣商品已成为社会的一大公害，对防伪技术产品的需求量也在持续增长，提高防伪的科技含量，杜绝假冒商品，显得尤为重要。数字水印技术为数据媒体的版权保护提供了有效的保障，符合产品防伪“难仿制、成本低、无公害”的综合性能要求，在包装防伪领域具有广阔的应用前景。但实际的打印或印刷工艺过程对印刷品图像本身是一种多源异类攻击，印刷品图像数字化过程所引起的失真会造成水印信息无法提取。全息图具有独特的不可撕毁特性，能有效地抵抗剪切、旋转等几何攻击。为此，本文将计算全息引入数字水印技术，以期达到提高商品防伪信息的破解难度和抵抗印刷过程中可能遭遇的各类攻击的能力。本文首先探讨了将普通数字图像转换为全息图的计算机生成算法。着重研究了三种全息图的生成与再现算法：罗曼型全息图、傅里叶全息图和菲涅耳全息图；并以傅里叶全息图为例，进行了模拟剪切和旋转攻击的仿真实验，验证了全息图抗攻击的鲁棒性。针对印刷及制版工艺特点，研究基于全息图的数字水印加密算法。根据CMYK分色制版及四色叠印的原理，提出了一种新的小波域全息数字水印算法。以菲涅耳全息图作为加密水印信息，对全息水印图像利用Arnold置乱变换进行二次加密处理，再将加密后的全息水印信息嵌入到基于Bresenham算法所选区域，以画圆半径作为嵌入密钥，实现了水印的第三重加密，从而有效地提高了防伪信息的安全性。昀后通过计算机模拟攻击，检验所设计的全息数字水印算法的鲁棒性。结果表明：该算法对图像滤波、缩小以及印刷加网攻击的鲁棒性不理想，但对图像加噪、曝光、剪切、放大、压缩和涂污等攻击具有非常好的鲁棒性。本文对全息数字水印技术在包装印刷品的防伪应用进行了有益的探索，所取得的成果为研究工作的进一步开展打下了良好的基础。关键词：数字水印，计算全息，全息数字水印，包装印刷防伪IIABSTRACTCommodityeconomyishighlycompetitive,andthecounterfeitorinferiorcommodityhasbeenacommonscourgetothecommunity.Anti-counterfeitingtechnologyproductsarecontinuousincreasing.Itisevenmoreimportanttostopfakecommoditieswithscientificandtechnologicalprogressandupgrades.Digitalwatermarking,effectivelyguaranteeingthecopyrightofdatamedium,conformstocomprehensivepropertyrequirementsofanti-counterfeitingtechnology,suchasdifficulttocopy,low-cost,non-pollution.Ithasawidefieldofapplicationprospectinanti-counterfeitingpackaging.However,printingisamulti-sourceheterogeneousattacktoprintingimage.Thewatermarkingcannotbeextractedbecauseofthedistortionduetothedigitizingprocessofprintings.Withauniquecharacteristicofnotbeingtoreup,hologramcaneffectivelyresistthecroppingandrotatingattack.Forthisreason,thispapercombinesdigitalimagewatermarkingwithholographictechnique,toenhancethedecodingdifficultyofproductsecurityinformationandtheabilitytoresistvarioustypesofattacksintheprintingprocess.Firstly,thispaperdiscussedthecomputerizedalgorithmbywhichacommondigitalimagecouldbeconvertedtoacomputer-generatedhologram(CGH).ThethreekindsofCGH,includingLohmann-CGH,Fourier-CGHandFresnel-CGH,havebeenstudiedparticularlyabouttheirgenerationandreconstructionofthealgorithm.Forexample,thesimulationthatFourier-CGHwascroppedandrotatedwasdone,andtheresultverifiedtheexcellentrobustness.Digitalwatermarkingencryptionalgorithmbasedonhologramisstudiedforcharacteristicsoftheprintingandplate-makingtechnology.AccordingtotheprincipleoftheprintinginCMYKcolorspace,anovelhologramdigitalwatermarkingtechniqueinDWTdomainwaspresented.Fresnelhologramwasusedasanencryptedwatermark,andthenitwassecondlyencryptedbyArnoldtransformation.TheencryptedhologramwatermarkingwasembeddedintothedomainbasedonBresenhamalgorithm,andthecircleradiuswasusedasembeddingkeytoachievetheIIIthirdencryptionforwatermarking.Sothesecurityofanti-counterfeitinginformationwaseffectivelyimproved.Finally,therobustnessofthedesignedhologramdigitalwatermarkingalgorithmwastestbycomputersimulatingattacks.Theresultsshowedthatthisalgorithmhadapoorrobustnessforattacks,suchasfiltering,reducingandprintingscreening,butithadanexcellentrobustnessforaddingnoise,exposure,cropping,enlarging,compressionanddoodling.Thesecurityapplicationofhologramdigitalwatermarkingtechnologyinpackagesprintinganti-counterfeitingwasvaluablyexploredinthispaper,andtheachievementofthispaperwillserveasfirmfoundationforthefurtherresearchwork.KeyWords:digitalwatermarking,computer-generatedhologram,holographicdigitalwatermarking,packageprintinganti-counterfeitingIV目录摘要.............................................................................................................................I ABSTRACT.................................................................................................................II 第一章绪论................................................................................................................1 1.1研究背景及意义.............................................................................................1 1.1.1传统的包装防伪技术...........................................................................1 1.1.2全息防伪技术.......................................................................................2 1.1.3数字水印技术.......................................................................................3 1.1.4数字水印在包装防伪中的应用...........................................................4 1.1.5全息数字水印技术...............................................................................5 1.2本文研究目的和内容.....................................................................................5 第二章数字水印及计算全息......................................................................................7 2.1数字水印技术.................................................................................................7 2.1.1数字水印原理.......................................................................................7 2.1.2数字水印的特性...................................................................................8 2.1.3数字水印的分类...................................................................................9 2.1.4数字水印的主要应用领域.................................................................10 2.1.5典型空间域水印算法...................