Fig. 1. Non-local image dehazing. (a) Haze-free image and corresponding clusters; (b) hazy image and corresponding haze-lines

Fig. 2. Haze-lines. (a) Haze image; (b) pixels marked in the original image formed a haze-line in RGB color space

Fig. 3. Estimation of initial transmission. (a) Haze image; (b) r(x); (c) r^max(x); (d) t~(x)

Fig. 4. Dehazing results using existing algorithms. (a) Initial haze image; (b) dehazing image of Ref. [11] method; (c) dehazing image of Ref. [13] method

Fig. 5. Comparison of the transmission optimization and the dehazing results. (a) Haze image; (b) Ref. [10] algorithm; (c) Ref. [9] algorithm; (d) proposed algorithm

Fig. 6. Dehazing results using different algorithms.(a) Haze images; (b) Ref. [10] algorithm; (c) Ref. [11] algorithm; (d) Ref. [9] algorithm; (e) Ref. [13] algorithm; (f) proposed algorithm

Fig. 7. Comparison of the edge regions. (a) Haze image; (b) Ref. [10] algorithm; (c) Ref. [13] algorithm; (d) Ref. [27] algorithm; (e) proposed algorithm