bin_threshold — Segment an image using an automatically determined threshold.
bin_threshold is obsolete and is only provided for reasons of backward compatibility. New applications should use the operator binary_threshold instead.
bin_threshold segments a single-channel gray value image using an automatically determined threshold. First, the relative histogram of the gray values is determined. Then, relevant minima are extracted from the histogram, which are used as parameters for a thresholding operation. In order to reduce the number of minima, the histogram is smoothed with a Gaussian, as in auto_threshold. The mask size is enlarged until there is only one minimum in the smoothed histogram. The selected region contains the pixels with gray values from 0 to the minimum or for real images from the smallest value to the respective minimum. This operator is, for example useful for the segmentation of dark characters on a light paper.
Dark regions of the image.
read_image (Image, 'letters') bin_threshold (Image, Seg) connection (Seg, Connected)