WatermarkingOverviewGoalsBit-Plane SlicingCox MethodComparisonSlide 7Methods of AttackReferencesQuestions?WatermarkingMatt ElliottBrian SchuetteOverview•Goals•Methods•Comparison•Attacks•ReferencesGoalsWatermark Goals•Robust•Invisible•RecoveryProject Goals•Watermark Types–Fragile–Robust•Techniques–Frequency Domain–Spatial domainBit-Plane Slicing•Spatial Domain•LSB contains watermark•Simple detection•Many options–Image blocks–Encode Text–Specific AreasCox Method–Frequency Domain–Transformation–AC Coefficients•Sorted by size•Largest 1000 selected•Psuedo-random watermark embedded–Reverse transformation2D DCT sort v’=v (1+ w)IDCT & normalizeOriginal imageN largest coeff.other coeff.marked imagerandom vector generatorwmkseedComparison•Fragile Watermark–Very susceptible to attack–Used for tampering detection•Robust Watermark–Resistant to tampering–Used with public images–Provides proof of ownershipBit-Plane SlicingMethods of Attack•Scaling•Cropping•JPEG•Print/XeroxReferences•ECE 738 Advanced Digital Image Processing•Professor Hu•Wikipedia•Digital Image Processing, Gonzalez and Woods•I. Cox, J. Kilian, T. Leighton, T. Shamoon: “Secure Spread Spectrum Watermarking for Multimedia'', IEEE Transaction on Image Processing, vol.6, no.12, pp.1673-1687,
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