Inter predictionIn HEVC, inter prediction is performed on the prediction block (PB) level. The corresponding prediction unit (PU) contains the information how inter prediction is performed.

Inter prediction is called motion compensated prediction since shifted areas of the reference pictures are used for prediction of the current PB. The resulting displacement between the area in the reference picture and the current PB is interpreted as the motion of the area between the reference picture and the current picture.

Motion compensated prediction can be performed using one or two reference pictures as the prediction source. The number of available prediction sources depends on the slice type of the slice the current PU belongs to.