| 摘要 |
PURPOSE:To improve vertical resolution, by forming the first sub-field formed at a speed of 2 times, by every other horizontal scanning line of a TV signal, and forming the second sub-field by the remaining every horizontal scanning line. CONSTITUTION:In case when a video signal of the upper half of an odd field is stored in an address of the upper half of an RAM5, at the point of time of the center of an odd field of a video signal, read-out is started from the uppermost address of the RAM5, and also the video signal of the lower half of the odd field is written in order in an address of the lower half of the RAM5. In this state, the read-out is executed as to every other address of each horizontal scanning line, by which a read-out address gradually approaches a write address, and at the point of time of the end of the odd field, both become in coincidence. By every other horizontal scanning line signal which is read out during this time, a video signal of the first sub-field is formed, and by the remaining horizontal scanning line, a video signal of the second sub-field is formed. In the same way, by an even field, a video signal of the third and the fourth fields is formed. |
