This invention includes image processing techniques directed to achieve feature enhancement and background-foreground enhancement in fingerprint images. The image is divided into plural segments depending on the ridge-valley directions. Each segment is separately filtered with a directional filter generally perpendicular to the corresponding ridge-valley direction. Background-foreground detection employs edge detection to identify edge pixels. These edge pixels are averaged to determine a threshold. The threshold is applied to the original image to determine background and foreground pixels. The background and foreground pixels are filtered via a watershed fill filter with separate connectivity for background and foreground pixels.