Patent Document ID: 9245310
Application ID: 13840107
Patent Status: 1

Claim One:
1. A method of watermarking a video, the method comprising: generating three or more pilot signals; generating a watermark; embedding the three or more of the pilot signals in a first set of frames of the video according to a pilot just-noticeable-difference (JND) model; and embedding the watermark in a second set of frames of the video according to a watermarking just-noticeable-difference (JND) model, the second set of frames being non-overlapping with the first set of frames, wherein: embedding the watermark comprises embedding the watermark in a Y luminance component of each of the second set of frames; and embedding the watermark in a Y luminance component of each of the second set of frames comprises, for each frame in the second set of frames; partitioning the corresponding frame into 8×8 blocks B(i,j), where 0≦i≦m, 0≦j≦n; generating an 8×8 pseudorandom block B r (x,y) having elements x, y=0, 1,. .. , 7 with a pseudo normal distribution N(0, 1); applying a discrete cosine transform (DCT) to each block B(i,j) of the corresponding frame to generate a corresponding DCT block C(x,v); and embedding the watermark in coefficients of each DCT block C(x,y) to generate a corresponding watermarked DCT block C w (x,y) according to an equation C w (x,y)=C(x,y)+s w ·W(i,j)·B r (x,y)·JND (x,y), where s w is a non-negative number representing watermarking strength, W(i,j) is a corresponding block of the watermark, and JND w (x,y) is a formula representing the watermarking JND model, and JND w (x,y)=max{C To (x,y), C To (x,y)|(C(x,y)/C To (x,y)| ε }, where C To (x,y)=Tf(x,y) x (DC/C 0 ) a , Tf(x,y) is half of a quantization step-size of C(x,y), DC is a discrete cosine coefficient, C 0 is a global mean of a luminance for 8-bit images, a=0.649 and ε=0.33.