MOTION VECTOR DETECTING METHOD AND SYSTEM FOR MOTION COMPENSATING PREDICTIVE CODER

摘要

In a method of detecting motion vector data indicative of motion of a partial area in an input picture from any area on a reference picture, a first distortion between a partial area constructed by fields of the input picture and a partial area constructed by fields of the reference picture is calculated as a first evaluation value; a position of the partial area constructed by the fields of the reference picture at which the first evaluation value becomes the minimum value is detected; a search windowon a frame of the reference picture is set on the basis of a detected position of the partial area constructed by the fields of the reference picture previously detected; and a second distortion between a partial area constructed by a frame in the set search window and a partial area constructed by a frame of the input picture is calculated as a second evaluation value, and a position of the partial area constructed by the frame of the reference picture at which the second evaluation value becomes the minimum value is detected. Therefore, the frame vectors can be detected on the basis of the field vector detection positions, so that the amount of calculations required to retrieve frame vectors can be reduced markedly, without degrading the detection precision of the frame vectors.