| 摘要 |
PURPOSE:To remove the flicker of a character picture and to obtain a fine and sharp picture by scanning at a speed of twice the ordinary horizontal scanning frequency, displaying the information of one frame during one field display period on the basis of signal interpolation and switching a signal interpolating method in accordance with the switching of reception of television broadcasting, character multi-broadcasting, a CAPTEIN system, etc. CONSTITUTION:A digital video signal converted by an A/D converter, character multi-broadcasting converted at its level and a digital character signal from the CAPTAIN system are outputted as an output multiplexed as their characters and videos by a character/video switching circuit 11. Although the sampling rate of the digital character signal is 8/5fSC, said sampling rate becomes 8/5X2fSC similar to the digital video signal by latching the digital character signal with a sampling clock of 8/5X2fSC by a clock rate converter 20. As to interpolation at the conversion into sequential scanning, the digital video signal is interpolated by the additive means of a scanning line, i.e. line insertion, and the digital character signal is interpolated by scanning the same scanning line twice.
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