Fine Colour Processing extracts a colour's hue, saturation, and brightness values. Stains are then processed as variances in any of these values. Gradual changes caused by seams or lighting variations on curved surfaces can then be factored out in order to eliminate false detections.
Colour extraction was used to detect flaws and foreign particles inside of paper cups, but seams were often detected as flaws. The CV-5000 Series Fine Colour Processing can adjust for gradual changes in colour such as a seam and extracts the stark differences in hue caused by a stain.