Abstract: The invention relates to a method and apparatus for vertically scaling a video picture comprising receiving and storing lines of a video frame of a video picture, reading lines of the frame into linestores, applying the lines to a vertical filter and providing an output video line as a function of the lines. Reading the lines of the frame into linestores comprises reading M lines of each successive 2nd line of the frame lines into the linestores. Following generation of the output video line, a further X lines are read from the framestore into the linestores to provide a further set of M lines in the linestores. The M lines are applied to the vertical filter to provide a further output video line as a function of the lines.