Patent ID: 6665418
Filing Date: 2003-12-16
Classification: G06T

Abstract:
In a method of embedding a hidden message in digital image data, wherein the method is described by: Iâ€²&it;â€ƒ&it;(x,y)=I&it;â€ƒ&it;(x,y)+&Sum;i=1n&it;â€ƒ&it;bi&CenterDot;Ri,where Iâ€²(x,y) is the digital data containing the hidden message,I(x,y) is the digital image data, n is the number of bits, where n is equal to or greater than 2, bi are the bits of the hidden message, and Rj are random arrays of numbers having the property that Ri&CenterDot;Rj={1where&it;â€ƒ&it;i=j0where&it;â€ƒ&it;i&NotEqual;j,the improvement comprising:Ri=C(xâˆ’&agr;i,yâˆ’&bgr;i) where C(x,y) is a array of random numbers, and(&agr;i,&bgr;i) are offsets having the property that (&agr;i,&bgr;i)â‰ (&agr;j,&bgr;j) for iâ‰ j; wherein the distance ((&agr;iâˆ’&agr;j)2+(&bgr;iâˆ’&bgr;j)2)0.5 between any two offsets is greater than the autocorrelation width of C(x,y).