MOVING IMAGE CODING APPARATUS, MOVING IMAGE DECODING APPARATUS, CONTROL METHOD THEREFOR, COMPUTER PROGRAM, AND COMPUTER-READABLE STORAGE MEDIUM

This technique prevents errors from being gradually accumulated on the decoding side, while maintaining high scalability, even when transformation to subbands as a plurality of frequency components is used for moving image coding. The image data of one input frame is decomposed into a plurality of subbands having different frequency components by a discrete wavelet transformation unit. A lower bitplane coding unit codes, for each bitplane, predetermined lower bits of each coefficient data of a subband LL and the coefficient data of subbands other than the subband LL. The data of the upper bits of the subband LL is stored in a frame memory. A motion vector detection unit detects a predicted value and motion vector on the basis of the decoded data of the subband LL in a preceding frame. A subtracter obtains the difference between the detected predicted value and the current frame.