A display system comprises a display panel substantially comprising a subpixel repeating group tiled across the panel in a regular pattern. The subpixel repeating group comprises at least one white subpixel and a plurality of colored subpixels. The display system further comprises input circuitry configured to receive input image data indicating an image for rendering on the display panel, and subpixel rendering circuitry configured to compute an output luminance value for each subpixel of said display panel. The subpixel rendering circuitry multiplies data values of a spatial portion of the input image data by at least one image filter kernel which comprises a matrix of coefficients arranged such that each coefficient represents a fractional part of one of said data values of said spatial portion of said input image data. The subpixel rendering circuitry is further configured to sharpen the output luminance values using a luminance signal.