PATTERN MATCHING is one of the most promising applications for configurable computing. FPGAs are particularly well suited for pattern matching because they can carry out comparisons using simple additions and shifts of individual bits. Pattern matching begins with a candidate image and the target image for comparison. The images are converted into binary templates, and the FPGA compares bits in the candidate image with those in the target template using a logical AND circuit. Another part of the device is configured as an adder to count the total number of pixels that are "on" (represented by 1's) in both templates. The higher the number, the better the match.

Image: Bryan Christie