A　novel　technique　for　estimating　traffic　visibility　based　on　homogenous　area　extraction　is　presented　in　this　paper.　Focusing　on　the　problem　of　detecting　daytime　fog　and　estimating　visibility,　this　proposed　algorithm　adopts　a　measure　defined　by　the　International　Commission　on　Illumination　(CIE)　as　the　distance　beyond　which　a　black　object　of　an　appropriate　dimension　is　perceived　with　a　contrast　of　less　than　5%.　The　key　step　for　the　algorithm　is　homogenous　area　extraction　including　sky　and　road　selection　from　the　top　to　the　bottom　of　traffic　image.　Traffic　meteorological　visibility　will　be　known　as　long　as　the　inflection　point＇s　location　of　this　area　is　found.　Camera　parameter　calibration　should　be　done　by　vanishing　points　calculation　based　on　painted　lines　detection.　At　last,　calibration　results,　inflection　point　and　traffic　meteorological　visibility　for　three　different　traffic　scenes　will　be　given.　Comparison　with　real　data　obtained　manually　verifies　the　effectiveness　of　the　algorithm.　Copyright　©　2013　Inderscience　Enterprises　Ltd.