A hybrid block motion compensation/adaptive overlapped block motion compensation apparatus for an encoding apparatus includes: a selector for selecting between a block motion compensation BMC and an overlapped block motion compensation OBMC with respect to a current block in units of pixels according to a set criterion; an adaptive motion compensator; a scan mode setter for scanning the current block in a plurality of set scan modes and establishing a scan mode causing a smallest number of transitions between the BMC and OBMC; and an information recorder for recording transition information at locations of the pixels corresponding to the transitions between the BMC and OBMC. A decoding apparatus is disclosed including: an interpreter for scan mode information of a current block and information about transitions between the BMC and OBMC for each of pixels of the current block; and an adaptive motion compensator for operating in units of the pixels.