| 摘要 |
PURPOSE:To obtain a negative picture with erased negative line and a picture with erased negative area by controlling a frame buffer write control means with a boundary detecting signal. CONSTITUTION:When a picture element address Pa(x,y), picture element luminance iformation Pi, a face identification number PSNO(x,y) and a picture element depth PDEP are transmitted from a graphic generator, only an existing element close to a visual point is decided as to be displayed by the decision of the depth value PDEP at a depth comparator circuit 2 at first. Then a boundary deciding circuit 10 is operated in case of the picture element to be displayed. A boundary deciding circuit 10 detects the boundary and also outputs an existing boundary signal and it is fed to a frame buffer write control circuit 11. The frame buffer write control circuit 11 processes properly the picture element luminance information Pi and transmits it to a frame buffer 4 in response to a line picture output request signal QL, a pattern output request signal QA in addition to a boundary detecting signal BT and an existing boundary signal (FS=1). |
