The present invention is applicable to a wavelet transform in JPEG 2000 and makes it possible to implement a convolution operation while reversibility is achieved. To this end, an implementation of a two-stage integer-type lifting operation shown in FIG. 28A is decomposed in the order of FIGS. 28B and 28C, and finally is separated into a real-number processing unit and integerizing processing unit as shown in FIG. 28C.