GRAPHIC DISPLAY SYSTEM ALLOWED TO DELIVER PARTIAL IMAGE

摘要

PURPOSE: To segment an optional partial image at high speed by utilizing a raster arithmetic function provided in a graphic display system. CONSTITUTION: An external shape which defines the partial image to be segmented from an original image which is stored in the storage area 10A of an APA memory 10 is plotted through the use of an external shape plotting device 121 and a dot pattern 11 expressing the plotted external shape is written in a work storage area 10B. Then, under the control of a controller 26, reading of the dot pattern 11 from the work storage area 10B of the APA memory 10 to a mask data generator 14 is executed. Mask data which set the area surrounded by the external shape dot pattern 11 to a non-mask state and the others a mask state. Then, unmasked image data are written in a transfer destination storage area 10C. Thus, the optional partial image is segmented from the original image at high speed.