నైరూప్య

Data Hiding Using Difference Expension Method

YASMEEN M.G,RAJALAKSHMI G

Ininverse order of datahidingtechniques,thevaluesoforiginal dataaremodifiedaccordingtosomeparticularrulesandtheoriginalhostcontentcanbeperfectlyrestoredafterextractionofthehidden dataonanotherside.Inthispaper,theoptimalruleofvaluemodificationunderapayloaddistortioncriterionisfoundbyusinganiterativeprocedure, andapracticalinverse order ofdatahidingschemeisproposed.Theembedded secret data,aswellastheauxiliaryinformationusedforcontentget back,arecarriedbythedifferencesbetweentheoriginalpixel valuesandthecorrespondingvaluesestimated fromthe neighbors.Here,the errors aremodifiedaccordingtotheoptimalvaluetransferrule.Also,theoriginalimageisdividedintoanumberofpixelsubsetsandtheauxil iaryinformationofasubsetisalwaysembeddedintotheestimationerrorsinthenextsubset.Areceivercansuccessfullypull outtheembeddedsecret dataand recovertheoriginalcontentinthe subsetswithanreverseorder.Thisway,agoodinverse order ofdatahidingperformanceis achieved.