Adaptive edge map threshold

摘要

A method for detecting edges includes calculating a gradient level value for each pixel of a digital image and assigning each pixel to one of a plurality of gradient bins based on the calculated gradient level value for each pixel, the gradient bins being defined by threshold levels. One or more of the gradient bins are assigned as edge bins, and one or more of the gradient bins are assigned as non-edge bins according to the number of pixels assigned to each gradient bin. Pixels in the one or more edge bins are identified as edge pixels, and pixels in the one or more non-edge bins are identified as non-edge pixels in an edge map. The one or more gradient bins are assigned such that a minimum number of pixels are identified as edge pixels and no more than a maximum number of pixels are identified as edge pixels.