A threshold algorithms automatically (or manually) determines a threshold to distinguish between foreground and background of an image. After the threshold has been computed or manually chosen selected, the algorithm marks any pixel with an intensity value greater than this threshold with "1" and any pixel with intensity lower than the threshold as "0". The result is a binary image which subsequently can be processed with the Connected Component Analysis Node to extract a labeling with separated segments. For details see: "Survey over image thresholding techniques and quantitative performance evaluation" (Sezgin04)