1. A method of de-interlacing a video field in which new pixels to be added to the said field are derived from temporally adjacent fields comprising the steps of forming a first new-pixel value from motion compensation of a pixel of an earlier field with a first motion vector; forming a second new-pixel value from motion compensation of a pixel of a later field with a second motion vector; wherein each of the first motion vector and the second motion vector is determined as a peak in a phase-correlation surface with the coordinates of the location of the peak representing vector components and the height of the peak giving confidence value; and combining the said first and second new-pixel values in dependence upon a comparison of respective confidence values associated with the said first and second motion vectors so as to obtain a value for a new pixel to be added to the said field to be de-interlaced.