The soot and smoke generated from the exhaust gas of vehicles traveling through expressway tunnels impede the field of view of drivers. To cope with this problem, ventilation equipment is installed, and for the efficient operation of the ventilation equipment, measurements are made with VI meter (visibility index meter). CCD cameras for monitoring are installed in major expressway tunnels in Japan. Thus both the initial cost and maintenance expenses can be kept to a minimum if these various sensors like a VI meter can be incorporated in a CCD (charge coupled device) camera. Methods for measuring transmittance of soot and smoke from CCD camera images were studied and a new algorithm that makes use of a veiling luminance was constructed. (A*)
Samenvatting