| 摘要 |
A video display apparatus of the present invention simultaneously displays a plurality of video images, which are overlapping with one another, on a display screen as a function of video data read out of a plurality of video memories without transferring the video data among the video memories. The video display apparatus includes three memory control units 71-73, which output clock signals CLK1 through CLK3 synchronous with three video signals RGB01-3 read out of three video memory units 61-63, respectively. A video signal switching unit 82 selects one of the three video signals while a clock signal switching unit 4 selects one of the three clock signals. A digital-to-analog converter 86 executes digital-to-analog conversion of the selected video signal using the selected clock signal. A video control signal generator 80 supplies read-permit signals HPIE1-3 and VPIE1-3 to the three memory control units 71-73 to alternate the video signals suppled to the display device. This results in displaying video images read out of the three video memory units 61-63 to be overlapped one upon another on the display screen.
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