1. A computer-implemented method for generating a series of pictures to be displayed on a screen, each picture having plural picture elements with picture element intensities which represent a part of a picture that has moved a sub-pixel distance, the method using picture element intensities of a preceding picture and a known motion vector to calculate picture element intensities of a current picture, comprising the steps of: determining two fractional parts, f and g, of a motion vector (x+f, y+g), such that -1/2&lt;f.ltoreq.1/2 and -1/2&lt;g.ltoreq.1/2; determining two integer parts, x and y of the motion vector based on the determined fractional parts, f and g; generating and storing coefficients (a.sub.-1. .. a.sub.1) using the determined fractional part f, such that: ##EQU4## generating and storing coefficients (r.sub.-1. .. r.sub.1) using the determined fractional part g, such that: ##EQU5## calculating a picture element intensity, q(n,k), for a picture element (n, k) in a current picture as a sum of previous pixel values of the preceding picture weighted by the stored coefficients (a.sub.-1. .. a.sub.1) and (r.sub.-1. .. r.sub.1), by computing: ##EQU6## where p(n+x+i,k+y+j) are a picture element intensities of the preceding picture; and displaying the calculated picture element intensity on a screen for each pixel on the screen.