The image processing device of the present invention maps signal values on
saturation segments to corresponding signals on an achromatic axis. In
conjunction with this, mapping of color signal present around the
saturation segments is mapped while preserving the continuity prior to
mapping. The image processing device determines the displacement level
entailed in mapping color signal surround a saturation segment so as to
be inversely proportional to distance from the saturation segments. Since
chroma of signals on the saturation segments change precipitously before
and after mapping, by mapping signal surround the saturation segments so
as to preserve the continuity of the original signals of signals surround
the saturation segments, chroma gradation of signals on the saturation
segments and signals around saturation segments can be preserved with a
high degree of accuracy.