Patent ID: 8203648

Claim:
A motion vector detecting apparatus for detecting a motion vector for each process-unit square data of an original picture frame, the motion vector detecting apparatus comprising: a storage unit that temporarily stores process-unit square data of a reference picture frame which is transferred from a prefetch memory, the prefetch memory temporarily storing the reference picture frame to be used to obtain a correlation for the original picture frame, the reference picture frame being transferred from a frame memory which stores frame data of a motion picture; and a controller that is connected to the storage unit to read out data from the storage unit and that, in encoding an interlace picture, changes over a reference picture in a field unit when the motion vector detection of a P-picture is performed, and changes over a reference picture in a frame unit when the motion vector detection of a B-picture is performed, and, changes over the original picture frame to perform the motion vector detection when a same reference picture is referred to by more than one of a B-picture and a P-picture.