01046279

Component

A Road Visibility Information System (RVIS) was developed that uses images transmitted by multiple closed-circuit television (CCTV) cameras to gather road visibility information. A feasibility study in the daytime during January and February 2006 was performed at a 40-km section of National Route 230 at Nakayama Pass in northern Japan. During those two months, RVIS calculated visibility scale (VS) and road visibility index (RVI) automatically, accurately, continuously and in a timely manner from road images recorded by multiple CCTV cameras. RVIS processed 90% of the images transmitted by ten CCTV cameras and stored weighted intensity of power spectra (WIPS), VS and RVI data in the database of road visibility information during the two months. RVI estimated by RVIS showed time-series behavior similar to that of the meteorological data (visibility range, precipitation, wind speed) observed at the top of Nakayama Pass. We also surveyed subjective evaluations of road visibility using road images taken by the CCTV cameras. The evaluations had little dispersion among subjects, and they correlated closely with the RVI. The first advantage of RVIS is its ability to accumulate road visibility information for long periods over a wide area. The second is its low cost, which results from its use of existing CCTV cameras. The only additional cost in implementing RVIS is software development, assuming that CCTV cameras are already installed. The third is the provision of visibility information to drivers and road administrators. The RVIS developed in this study is expected to show reliable collection of road visibility data from images transmitted by multiple CCTV cameras. We will be working on developing a method for calculating the nighttime VS and on refining visibility prediction techniques using VS.

01042056

07-2275

English

20p

2007

Transportation Research Board 86th Annual Meeting

CD-ROM

Figures (9) ; References (9) ; Tables (1)

Closed circuit television; Data collection; Feasibility analysis; Image analysis; Information systems; Information technology; Night visibility; Night vision; Time series; Visibility; Visibility distance

Japan

Data and Information Technology; Highways; Safety and Human Factors; I82: Accidents and Transport Infrastructure

Transportation Research Board Annual Meeting 2007 Paper #07-2275

TRIS, TRB

Feb 8 2007 6:58PM