An image processing apparatus comprising: motion vector detection means for detecting a motion vector (V 0 (i, j)) of a subject pixel at a predetermined space position (i, j) of a frame at a predetermined time from an input image of a plurality of temporally different frames and for obtaining a reliability (C(i, j)) of the motion vector as a function of the difference absolute value sum (D(i, j)) between a subject block corresponding to the motion vector and a candidate block, the function being such that the smaller the difference absolute value sum, the greater the reliability; motion vector evaluation means for obtaining, at each space position (i+m, j+n) of neighbouring pixels within a predetermined range (M, N) of the subject space position of the subject pixel, an evaluation value (P (i+m, j+n)) of the motion vector (V 0 (i+m, j+n)) at the space position, said range including the subject space position, the evaluation value being obtained as the product of the reliability at the space position and a weight corresponding to the distance from the subject space position such that the evaluation value increases with respect to the motion vector which is nearer to the subject space position and has a higher reliability; and motion vector correction means for correcting the motion vector at the subject space position on the basis of the evaluation values and the motion vectors at the space positions of the predetermined range, the corrected motion vector being obtained by dividing the grand total of the products of the values of the motion vectors and the evaluation values of the neighbouring pixels by the grand total of the evaluation values of the neighbouring pixels. motion vector detection means for detecting a motion vector (V 0 (i, j)) of a subject pixel at a predetermined space position (i, j) of a frame at a predetermined time from an input image of a plurality of temporally different frames and for obtaining a reliability (C(i, j)) of the motion vector as a function of the difference absolute value sum (D(i, j)) between a subject block corresponding to the motion vector and a candidate block, the function being such that the smaller the difference absolute value sum, the greater the reliability; motion vector evaluation means for obtaining, at each space position (i+m, j+n) of neighbouring pixels within a predetermined range (M, N) of the subject space position of the subject pixel, an evaluation value (P (i+m, j+n)) of the motion vector (V 0 (i+m, j+n)) at the space position, said range including the subject space position, the evaluation value being obtained as the product of the reliability at the space position and a weight corresponding to the distance from the subject space position such that the evaluation value increases with respect to the motion vector which is nearer to the subject space position and has a higher reliability; and motion vector correction means for correcting the motion vector at the subject space position on the basis of the evaluation values and the motion vectors at the space positions of the predetermined range, the corrected motion vector being obtained by dividing the grand total of the products of the values of the motion vectors and the evaluation values of the neighbouring pixels by the grand total of the evaluation values of the neighbouring pixels.