An image coding method is provided, in which the method includes the steps
of: extracting edge information which represents an edge part of an
original image; obtaining density information of an edge smoothed image
from the original image by smoothing the edge part; obtaining coded edge
information by coding the edge information according to a first coding
algorithm; obtaining coded density information by coding the density
information of the edge smoothed image according to a second coding
algorithm; and sending the coded edge information and the coded density
information as coded information to an image decoding apparatus.