Haze-degree Corresponding ω¯ Standards
Haze area proportion Haze density
0 0.1 0 clear
1 0.3 0 80% thin
2 0.5 0 80% normal or thick
3 0.7 80% 100% thin
4 0.8 80% 100% normal
5 0.9 80% 100% thick
Table 1: Standards dividing images into six groups.