Editing Marr–Hildreth algorithm (section)

==Limitations==
The Marr–Hildreth operator suffers from two main limitations. It generates responses that do not correspond to edges, so-called "false edges", and the localization error may be severe at curved edges. Today, there are much better edge detection methods, such as the [[Canny edge detector]] based on the search for local directional maxima in the gradient magnitude, or the differential approach based on the search for zero crossings of the differential expression that corresponds to the second-order derivative in the gradient direction (both of these operations preceded by a Gaussian smoothing step). For more details, see the article on [[edge detection]].