A method and apparatus of encoding digital video according to the ISO/IEC MPEG standards (ISO/IEC 11172-2 MPEG-1 and ISO/IEC 13818-2 MPEG-2) using an adaptive motion estimator. A plurality of global motion vectors are derived from the motion vectors of a previous picture in a sequence, and the global motion vectors are analyzed to determine motion characteristics. The video encoding is arranged to enable switching among different types of local motion estimators based on the motion characteristics of the moving pictures sequence. This gives rise to a motion estimation algorithm that can adaptively change its search range, search area and block matching scheme to suit different types of moving sequences.