Patent ID: 6421464
Filing Date: 2002-07-16
Classification: G06F,H04N

Abstract:
An apparatus for coding, storing or transmitting, and decoding MÃ—M sized blocks of digitally represented images, where M is an even number comprisinga. a forward transform comprising i. a base transform having M channels numbered 0 through Mâˆ’1, half of said channel numbers being odd and half being even; ii. an equal normalization factor in each of the M channels selected to be dyadic-rational; iii. a full-scale butterfly implemented as a series of lifting steps with a first set of dyadic rational coefficients; iv. M/2 delay lines in the odd numbered channels; v. a full-scale butterfly implemented as a series of lifting steps with said first set of dyadic rational coefficients; and vi. a series of lifting steps in the odd numbered channels with a second specifically selected set of dyadic-rational coefficients; b. means for transmission or storage of the transform output coefficients; and c. an inverse transform comprising i. M channels numbered 0 through Mâˆ’1, half of said channel numbers being odd and half being even; ii. a series of inverse lifting steps in the odd numbered channels with said second set of specifically selected dyadic-rational coefficients; iii. a full-scale butterfly implemented as a series of lifting steps with said first set of specifically selected dyadic-rational coefficients; iv. M/2 delay lines in the even numbered channels; v. a full-scale butterfly implemented as a series of lifting steps with said first set of specifically selected dyadic-rational coefficients; vi. an equal denormalization factor in each of the M channels specifically selected to be dyadic-rational; and vii. a base inverse transform having M channels numbered 0 through Mâˆ’1.