Patent ID: 7844072

Claim:
A method of embedding a watermark in a motion image signal, the motion image signal comprising a sequence of images, the method comprising: representing the watermark by a sequence of watermark samples each having a value; dividing an image of the sequence of images into at least a first and a second image area; modifying the image in accordance with a watermark sample from the sequence of watermark samples, the modification comprising adding the watermark sample value to the luminance value of pixels of the first image area and subtracting the watermark sample value from the luminance value of pixels of the second image area to oppositely modify the mean luminances of the first and second image areas in accordance with the watermark sample; and for each of the sequence of watermark samples, repeating the dividing an image of the sequence of images and modifying of the image in accordance with a watermark sample from the sequence of watermark samples such that each watermark sample oppositely modifies the mean luminances of the first and second image areas of a different image of the sequence of images until the entire watermark is embedded.