IMAGE CODER AND IMAGE CODING METHOD

摘要

PROBLEM TO BE SOLVED: To eliminate block distortion by reducing an arithmetic amount for calculating a motion vector in the image coding. SOLUTION: A frame field conversion section 10 separates an interlace image for each field and an inter-field wavelet transform section 12 applies wavelet transformation to each field. That is, a plurality of odd number or even number fields in time series are used for one group and pluralities of the fields are wavelet-transformed to be separated for each spatial frequency. A motion vector in common to each group is calculated from a time change in an optional image component among a plurality of images separated for each spatial frequency to conduct motion compensation. The image subject to inter-field wavelet transform is given to an in-field wavelet transform section 14, where wavelet transformation is conducted and coded.