Video image creation system which proportionally mixes previously

Abstract

Video image creation in which a raster-scan monitor displays an image comprising realistic, inherently non-aliased strokes created by combining proportions of the values of: (i) pixels defining a simulated brush moving along the image as an artist moves a pen on a tablet in continuous strokes; and (ii) the values of the pixels in the image that are under the brush at the time. The pixel values resulting from such combining replace the corresponding pixel values in the image so that, after an initial portion of a stroke, the pixel values in the image which are under the brush and therefore will be combined with the brush values comprise pixel values which are the cumulative result of a number of previous such combining operations. Manual pressure on the pen controls the proportions used in such combining operations. As the artist presses harder on the pen, the effect seen on the monitor is that more 'paint' is applied. Image creation takes place substantially in real time, to retain the feel of conventional drawing or painting while providing the benefits of the electronic medium. The brush position on the image can be defined to sub-pixel resolution to improve the process. In an air brush mode, dwell time rather than movement of the pen initiates new pixel value combining operations.