Digital video correlator for e,g, aircraft guidance system - has single-bit correlators for comparing digitised valves of live and reference images in shifting network

摘要

Tbe digital video correlator includes a video digitiser which divides liVe and reference images from various sources into picture elements and digitises those elements to fixed voltage leVels. The digitised live image is passed to a dynamic memory consisting of interconnected shift registers while the digitised reference image is maintained within a first set of sbift registers comprising a portion of a processor. A second set of shift registers within the processor maintain a mask function. Yet a third set of shift registers within the processor are interconnected in parallel to the dynamic memory to receive, under control of a clock, the digitised data of the live image. As the live image data is shifted through the tbird set of shift registers, single-bit correlators interconnecting corresponding bits of each of the first, second, and third sets of shift registers, compare the digitised values of the corresponding bits, witb such comparison being enabled or negated by the mask function.