A method for video blending of graphics and video content for a display system, the method comprising: rendering one or more graphics items for display with the video content; generating a series of graphics planes containing the rendered one or more graphics items, the series of graphics planes comprising; a first graphics plane with a first dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the first dither pattern; and a second graphics plane with a second dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the second dither pattern, wherein the second dither pattern is different from the first dither pattern; receiving the video content as a series of video overlay planes; generating, with a hardware processor, a series of video frames comprising a time-averaged blending of the one or more graphics items and the video content by combining each video overlay plane of the series of video overlay planes with one of the first graphics plane and second graphics plane in alternating fashion between the first graphics plane and the second graphics plane, the combining of a video overlay plane with one of the first graphics plane and the second graphics plane being achieved by drawing a pixel from the graphics plane unless the colour value of said pixel matches the color key, otherwise drawing the pixel from the video overlay plane instead, to create a time-averaged partial transparency effect of the one or more graphics items with respect to the video content; and outputting the series of video frames for display on the display system. rendering one or more graphics items for display with the video content; generating a series of graphics planes containing the rendered one or more graphics items, the series of graphics planes comprising; a first graphics plane with a first dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the first dither pattern; and a second graphics plane with a second dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the second dither pattern, wherein the second dither pattern is different from the first dither pattern; a first graphics plane with a first dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the first dither pattern; and a second graphics plane with a second dither pattern of colour keyed pixels applied to it, by which applying the colour of those pixels from the rendered graphics are replaced by the color key value, at pixels where the colour key value is present in the second dither pattern, wherein the second dither pattern is different from the first dither pattern; receiving the video content as a series of video overlay planes; generating, with a hardware processor, a series of video frames comprising a time-averaged blending of the one or more graphics items and the video content by combining each video overlay plane of the series of video overlay planes with one of the first graphics plane and second graphics plane in alternating fashion between the first graphics plane and the second graphics plane, the combining of a video overlay plane with one of the first graphics plane and the second graphics plane being achieved by drawing a pixel from the graphics plane unless the colour value of said pixel matches the color key, otherwise drawing the pixel from the video overlay plane instead, to create a time-averaged partial transparency effect of the one or more graphics items with respect to the video content; and outputting the series of video frames for display on the display system.