| 摘要 |
A hard copy of a video frame represented by periodic video signals is obtained by dividing the range of amplitude of the video signals into N levels, converting the video signals into N two-level brightness distributions on the screen of a monochromatic CRT under the condition that a pixel in the ith distribution has the upper of two levels only if the level of the video signal representing the corresponding pixel in the frame exceeds the ith level, and exposing a photosensitive sheet to light from the screen. Thus, each pixel on the sheet is exposed to light of predetermined brightness for a period of time functionally dependent on the level of the video signal represented by the corresponding pixel in the frame.
|
