IMAGE PROCESSING DEVICE AND METHOD

摘要

PROBLEM TO BE SOLVED: To improve the image quality by checking a local property of an image whose image quality is deteriorated by coding so as to control the strength of smoothing of a filter thereby making image quality deterioration unremarkable. SOLUTION: An image signal whose image quality is deteriorated by coding is received by an input terminal 11. A image signal whose image quality is deteriorated by the coding received from the input terminal 11 is given at first to an area division means 12, in which the signal area is divided into small areas. The area division is made by the same size of a square block size equal to that for DCT coding. The image signal subject to area division into blocks is given to a filter control means 13 and a filter 14. Then the filter control means 13 generates a signal S to increase the smoothing as a difference between a maximum value and a minimum value of a picture element value in the divided image area is larger and to increase the smoothing as a difference between a maximum value and a minimum value of a picture element value in the divided image area is smaller. The filter 14 changes the strength of smoothing by the signal S to apply filtering processing to an input image signal.