| 摘要 |
<p>PURPOSE:To reduce ringing or glitter at both edges of a picture by relaxing the amplitude change of a video signal at both edges of the picture when a video signal with a different aspect ratio is displayed. CONSTITUTION:A signal converter 73A is provided, which applies scanning conversion to signal of the high definition television system and a signal of the existing standard television system based on the vertical length of the screen of the high definition display device and generates a signal 11 controlling the contrast for a prescriber period for the start and end of the video signal within one horizontal period. In the case of displaying the picture of the existing standard television signal onto the screen 76 of the high definition television receiver, a contract adjustment circuit 12 changes the video signal at both edges of a picture gradually. Thus, the amplitude change at a boundary of the video signal is relaxed and ringing and glitter both edges of the picture are reduced.</p> |
