| 摘要 |
In order to display a video signal having an aspect ratio of 4 to 3 on a video display screen having a 16 to 9 aspect ratio a nonlinear vertical deflection signal is used to compress the video image along the top and bottom edges of the 16 to 9 aspect ratio screen. The video image is compressed only along the top and bottom edges of the screen because it has been found that motion of the point of view of the viewer relative to the displayed image is generally horizontal but is infrequently vertical. One approach to providing the non-linear vertical deflection waveform is to detect whether the input video signal for display on a 16 to 9 aspect ratio screen is a 4 to 3 aspect ratio signal and, if so, to read out special, non-linear data from a memory. This special waveform data is used to generate the non-linear vertical deflection waveform. If the input video signal is detected to be a 16 to 9 aspect ratio signal, standard data is read out from the memory to be used to generate the appropriate linear vertical deflection waveform. <IMAGE> |
