| 摘要 |
PROBLEM TO BE SOLVED: To detect water droplets with high accuracy by imaging a supervisory space through the use of environment light outdoors in the daytime or the like. SOLUTION: A background difference arithmetic section 32 takes a difference between a background image and an input image imaged through the use of the environment light, and generates a difference image wherein the luminance difference between both the images is a prescribed value or over, an input high luminance difference image for satisfying a condition wherein pixels of the corresponding input image in the difference image have prescribed luminance values or over, and an input non-high luminance difference image satisfying a condition wherein pixel values of the corresponding input image in the difference image are less than prescribed luminance values. A water droplet candidate image generating section 34 generates an input weak edge image for satisfying a condition wherein the edge strength in the input image is a prescribed value or below and an edge reduced image whose edge strength is reduced more than that in the background image, and applies AND operation between at least one of the difference image, the input high luminance difference image and the input non-high luminance difference image, and an image resulting from ORing the input weak edge image and the edge reduced image so as to generate a water droplet candidate image wherein the water droplets exist with high possibility. A water droplet discrimination section 37 discriminates the presence/absence of the water droplets on the basis of the water droplet candidate image to detect the water droplets. COPYRIGHT: (C)2006,JPO&NCIPI |
