| 摘要 |
PURPOSE:To enlarge a picture, by delaying an input clock signal by means of a delay circuit and, at the same time, taking the exclusive 'OR' of the input clock signal and its delayed signal and using the exclusive 'OR' as the scanning clock of image information. CONSTITUTION:At the time of enlargement, outputs of an inverter 17 become '1' and delayed clock signals are outputted from an AND gate 18 and the outputs and clock signals are given to an EX-OR gate 15. After taking the exclusive 'OR' of the outputs and clocks, the EX-OR gate 15 generates clock signals, whose speed is twice as faster as the speed of the input clock signals, and enlarges a picture. Since picture enlargement can be realized with such a simple constitution, the circuit can be made smaller in scale and its cost can be reduced. Moreover, the converting time can also be reduced, because no line memory is used and time requirement for enlargement due to a line memory is eliminated.
|
