Automatic Centering Unit for the Registration of a Three-Tube Color Television Camera

Precise centering of the several images of a color television camera is difficult to maintain for long periods. A digital system is described which detects and corrects the centering errors from the video signals of normal scenes. In this system the video is converted to short pulses representing high-level, sharp edges of objects and the horizontal centering errors are then detected by comparing these pulses for relative time differences. Vertical errors are detected by a similar system which operates from line to line on signals recreated from the pulses by line-strobing. These signals contain vertical errors only. High-quality integrating stores are used to extract the average corrective powers from the error signals. The dc voltages thus obtained are then used to modify the appropriate centering control voltages.

Print ISSN

0361-4573

Published

1972-01

Content type

Original Research

DOI

10.5594/J05667