Correlator Operation
Images or data sets to be compared are arranged within a working resolution area (typically megapixel or more) and displayed in phase on a liquid crystal microdisplay, known as a Spatial Light Modulator.
For standard processes, a reference image (e.g. from a database/library) is typically compared with an input image (e.g. from an external camera), although any number of images may be entered and compared in the same process with no increase in processing time. The output contains information relating to the similarity and relative positions of the structures within the images or 2-D data sets.
However, the system may also be used as a comparator, by comparing the current and previous frames from a video stream. This has the hugely attractive advantage of detecting movements or relative shifts between frames, with no knowledge required of the structures within the images – a totally passive tracking system.
The correlator system is effectively a black box, which accepts high-resolution image or 2-D data sets and outputs a string of data containing the intensity (I) and positional data (x,y) relating to the matches found within the original data.
