A class sorting section obtains a class code CL indicating a class to which pixel data y of a target position in an image signal Vb belongs using motion compensation vector information mi stored in a buffer memory in pair with pixel data of an image signal Va corresponding to the pixel data y. An estimated prediction calculation circuit obtains the pixel data y based on an estimation equation, using pixel data xi of a prediction tap and coefficient data Wi read from a coefficient memory. The coefficient data Wi has been obtained beforehand by a learning executed by use of a student signal which corresponds to the image signal Va and contains the same encoded noise as of the image signal Va, and a teacher signal which corresponds to the image signal Vb and contains no encoded signal.