| 单词 | scanning |
| 释义 | scanning The process of refreshing a video screen. Interlaced scanning, which is used with most analog TV systems, involves two fields. Odd lines (field 1) are refreshed in one scan, and even lines (field 2) in the next. Each set of odd and even lines refreshed constitutes a frame refreshed. The scanning rate is a function of the power source of the receiver. For example, the American NTSC standard provides for 30 fps, involving 60 scans, which relates directly to the 60 Hz of the United States power source. The European PAL standard provides for 25 fps, involving 50 scans, which relates directly to the 50 Hz of the European power source. Progressive scanning involves displaying all horizontal scan lines in one frame at the same time, which avoids the problem of interline flicker. See also frame rate, NTSC, and PAL. |
| 随便看 |
|
科学参考收录了5291条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。