77Setting CheckersChapter 6OverviewPreprocessing(Setting value) Before preprocessing After preprocessingDilat. ->Eros. After removing dark (or black) noises, return the expanded area to its original size.3x3 / 5x5Median Removes light or fine noises by making the image of the object standing out againstbackground.3x3Smoothing Blurs the image. By doing so, the PV310 can easily measure the position of the objectwithout being affected by the noises.3x3 / 5x5Gray cut Reorganizes the grayscale range into the one between 0 and 255. This function is effectiveif there are any light or dark noises in the background, or if the contrast of the image of theobject is low.Min. /Max.Sobel Same as “Prewitt”. More easily extracts the area of lower contrast.3x3 / 5x5Prewitt Extracts the area of which grayscale has been changed. Only the outlines and edgesof the object are extracted.3x3 / 5x5