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Best Practices for Road Weather Management Version 2.0


Measurement of Motorist's Relative Visibility Index (MRVI) Through Video Images


This paper introduces a new road visibility index referred to as the motorists' relative visibility index (MRVI). This index represents the amount of visual information lost to the view of motorists due to atmospheric conditions in relation to the visual information available on an ideal clear day. MRVI is computed using readily available video images of roadways using relatively simple image processing techniques. MRVI is a road condition indicator and can be used for control of DMS, analysis of visibility effects on motorists, road closure decisions, and for fast identification of low visibility areas or time periods from a very large set of images collected from multiple video cameras.


81st Transportation Research Board (TRB) Annual Meeting, University of Minnesota-Duluth. For an electronic copy of this resource, please direct your request to

Date: 2002




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