Patent ID: 6983050

Claim:
A method of generating encrypted analog first, second and third signals (R′, G′, B′, respectively) from first, second, and third analog input signals (R, G, B, respectively) the method comprising: pseudo-randomly generating at least one of a plurality of matrix coefficients a 1 , a 2 , a 3 , b 1 , b 2 , b 3 , c 1 , c 2 , c 3 ; using an encryption circuit to perform a matrix multiplication operation to generate the encrypted analog first, second, and third signals, according to the following equations: R′= a 1 R+B 1 G+c 1 B G′= a 2 R+b 2 G+c 2 B B′= a 3 R+b 3 G+c 3 B wherein the matrix coefficients are generated such that each of the R′, G′ and B′ signals will be the product of summing two signals in the set of analog signals R, G, B and subtracting one of the signals in the set of analog signals R, G, B.