When obtaining subband signals by performing multiresolution decomposition on image data using a broad-sense pinwheel framelet or a pinwheel wavelet frame, having a degree, that is a set of an approximate filter with no orientation and a plurality of detail filters with respective orientations, and acquiring processed image data by the subband signals in a decomposition phase of the multiresolution decomposition, or processed image data that has been reconstructed into an image by summing the subband signals in a synthesis phase of the multiresolution decomposition, the present invention performs attenuation or amplification of the subband signals in the decomposition phase of the multiresolution decomposition that correspond to at least one of the filters.