Abstract: A method of implementing a fast video encoder by approximating a frame motion vector is introduced. MPEG-2 encoding uses both field and frame vectors in the encoding process. To implement an encoder in an efficient manner, an approximated motion vector created from two field motion vectors is used. The frame motion vector may be determined using the two field motion vectors alone, or by using the two field motion vectors in conjunction with their respective absolute error values. By using the disclosed methods, a motion estimation part for generating frame motion vector is not necessary. Only two field motion estimation parts are required to determine the field motion vectors, the frame motion vector is then approximated using the two field motion vectors. The cost and complexity of a digital video encoder system is thereby reduced.

Abstract: In order to detect a motion vector representing a movement of an objective area in a first image of a plurality of successive images, first, a plurality of comparison areas are determined in a second image before or after the first image. Subsequently, a difference total sum between the objective area and each of the comparison areas is obtained with respect to the plurality of comparison areas, thereby obtaining a distribution of the difference total sums. The resultant distribution of the difference total sums is approximately expressed in the form of a predetermined polynomial. By using this polynomial, the position is obtained where the difference total sums become minimum. By treating the resultant position of the area as the position before or after the movement of the objective area, the motion vector representing the movement of the objective area is detected.