Patent ID: 7940954
Filing Date: 2011-05-10
Classification: G10L,H04N

Abstract:
1. A method of making a watermarked digital representation of a signal from an original digital representation thereof, the method comprising the steps of: making a first transformation of the original digital representation to produce a first intermediate digital representation; adding watermark information to the first intermediate digital representation; and reversing the first transformation, the first transformation having the property that making and reversing the transformation spreads the watermark information across the original digital representation; wherein: the original digital representation and the watermarked digital representation belong to a first domain which is either the time/space domain or the frequency domain; and the step of making the first transformation includes the step of making a second transformation into a second domain which is the opposite of the first domain and the step of reversing the first transformation includes the step of making a third transformation into the second domain.