Patent ID: 7158655

Claim:
A system for detecting a fingerprinting word comprising: means for receiving a protected object that has embedded therein a fingerprinting word that contains a plurality of spread spectrum chips that are arranged in individual blocks that define individual spread sequences; and means for processing the protected object sufficient to identify an entity that is associated with the fingerprinting word, said entity comprising a potential colluder, wherein said means for processing comprises: means for calculating a weight for each block; and means for restricting the weights of certain blocks to a predetermined value, wherein said means for calculating comprises means for determining the weight of a block of an original spread sequence block value in accordance with the following equation: Let x∈{1, −1} and y∈{0, 1, −1}; f(y, x)=1 if x is not equal to y and y is not equal to 0, 0 Otherwise. Let X=(x 1 , . . . , x d ), where x i ∈{1, −1} and Y=(y 1 , . . ., y d ), where y i ∈{1, −1, 0}. The weight of Y relative to X is w(Y, X)—which is the sum from i=1 to d of f(y i , x i ), where “d” is the number of chips in each block.