An image processing apparatus in which output pixels of an output image are generated with respect to input pixels of an input image, a first subset of the output pixels being identical to respective input pixels and a second subset of the output pixels being derived from respective groups of one or more input pixels. The apparatus includes a spatial filter arrangement for filtering the second subset of pixels, the filter not being applied to filter the first subset of output pixels, the filter arrangement having a response such that high spatial frequencies are attenuated in the output image.