Patent ID: 7379500

Claim:
A method for image data compression, comprising: Approximating at least one non-power-of-2 element of a base matrix as a power-of-2 element such that all elements of a resultant matrix T 2 are power-of-2 elements, wherein the resultant matrix T 2 is: T 2 = ( 1 1 1 1 1 1 1 1 a b c d - d - c - b - a e f - f - e - e - f f e c d - a - b b a - d - c 1 - 1 - 1 1 1 - 1 - 1 1 b - a - d c - c d a - b f - e e - f - f e - e f d - c b - a a - b c - d ) wherein further, for floating point coefficients a, b, c, d, e, and f: a≧b≧c≧d and e≧f, a=2, b=2, c=1, all d=½ or all d=¼, e=2 and f=1; and encoding video data using the resultant matrix T 2 .