A white line detection apparatus comprises an extraction device that extracts
an
image of a white line detection processing area set within a road image captured
by an image-capturing device, a maximum value estimating device that estimates
a maximum value among pixel values constituting an image of road surface areas
other than the white line based upon the pixel values representing the image extracted
by the extraction device, a contrast reducing device that reduces the contrast
of an image corresponding to pixel values equal to or lower than the maximum value
among the pixel values constituting the image of road surface areas other than
the white line which has been estimated and a detection device that detects the
white line based upon the image whose contrast has been lowered by the contrast
reducing device.
