| 摘要 |
PURPOSE:To quicken the transfer by providing a color extracting circuit on a transfer rate so as to transfer the information of the extracted or thrown- away result to a main storage device. CONSTITUTION:A plane 2-0 on a video memory 1 corresponds to red, a plane 2-1 to green and a plane 2-2 to blue,and when video information in which only a red color, e.g., is thrown away as to a video graph is written in a main storage device 3, logical 0 is set to 'color factor 0' and logical 1 is set respectively to color factors 1,2. Then comparator circuits 9-0-9-2 output respectively a coincident component and an extraction detecting circuit 10 neglects the output from the comparator circuit 9-0. The signal is processed in the unit of 4-bit at a color extraction circuit 4, the result is arranged in the unit of 16 bits at a shifter 7 and then fed to the main storage device 3. A DMA control section 5 applies the timing control and the supply of address information during this time. Only the color boundary part is extracted and transferred, then 'edge detection' is commanded to the circuit 10 causing it to extract the boundary only. |
