Patent attributes
An encoder determines a filter to be used for deblocking filtering from among a plurality of filters including a first filter and a second filter. The first filter uses M pixels located at an upper side of the block boundary and M pixels located at a lower side of the block boundary, and the second filter uses first pixels located at the upper side of the block boundary and second pixels located at the lower side of the block boundary, where M is an integer of at least 2. The number of the first pixels is any one of a plurality of first candidate values, and the number of the second pixels is any one of a plurality of second candidate values. The plurality of first pixel candidate values and the plurality of second pixel candidate values are each a value greater than or equal to M.