Patent ID: 7747094

Claim:
An image coding apparatus comprising: motion compensation predicting means for generating a motion-compensated prediction image by detecting movement amounts in predetermined first partial image regions of an input image with respect to a reference image; smoothing means for performing smoothing of pixels located at the boundaries of adjoining images of the first partial image regions, with respect to the motion-compensated prediction image obtained by the motion compensation predicting means; and prediction residual coding means for coding a prediction residual signal obtained from a difference between the input image and the smoothed prediction image, wherein the smoothing means further comprises, activity level setting means for determining an activity level of second partial image regions of the input image; adaptive smoothing means for establishing an intensity of the smoothing on a basis of the activity level set with said activity level setting means, and for performing smoothing of pixels located at the boundaries between adjoining images of the first partial image regions; and post-processing means for performing suppression processing of a result of smoothing by using a threshold value established in accordance with said activity level, wherein the first partial image regions are larger in size than the second partial image regions, so that at least one second partial image region fits into one of the first partial image regions, and at least one of the second partial image regions overlap a boundary of two adjacent first partial image regions when determining said activity level by the activity level setting means, and the second partial image regions are arranged in a cross-like pattern, having a central block with two blocks arranged above and below the central block, and two other blocks arranged to the left and the right of the central block.