Edge detection schemes highly suitable for hardware implementation

Two schemes for edge detection of real images based on gradient maxima are presented. Images are filtered with narrow filters to increase localization. Experimental results and theoretical considerations suggest that the exact shape of the filter is not critical for good performance of the algorithm. Therefore a filter can be chosen to allow for a highly efficient hardware implementation, for example, a binary filter or a 4-bit finite-impulse-response filter. Because the digitized values of a binary filter are powers of 2, the hardware implementation does not require time-consuming computations, such as multiplication and time shift, but just appropriate addressings. The performance of this scheme, or a similar scheme using 4-bit filters, is as satisfactory as that of more sophisticated schemes. Therefore these low-cost schemes are likely to be more suitable for hardware implementation.