Abstract: There is provided a main memory (110) for storing a pictorial image constituted by pixels arranged on an XY plane, wherein a train of pixels arranged in an X-direction is defined by a runlength data (c, a) expressed by a color value c that a pixel has and a value a which can indicate the termination of an arrangement of pixels having the same color value. There are also provided a disk unit (200) for retaining data given to said main memory in the form of runlength data as they are, data form conversion unit (130) for converting runlength data in the main memory to raster data, a frame memory (120) for retaining the raster data converted at the data form conversion unit in order to display pictorial images on a visual display (400), and a pictorial image processing unit (140) for implementing a pictorial image processing operation to runlength data in the main memory. The pictorial image processing unit (140) includes a coloring processing section (141) and a draw processing section (142).