# Saturation-Based Airlight Color Restoration of Hazy Images
## 4 Experimental Results and Discussions
### Visual Comparison of Various Hazy Images
The assessment of the visibility improvement performance in Figure 11 shows that HRDCP and NGCCLAHE resulted in a bluish haze that is clearly seen in tests 1 and 3, through which poor visibility from the original image could be verified. Further, HRDCP and NGCCLAHE failed to preserve the saturation of the object and scene in all tests, except in test 5, and as such, the distant scenes became blurry. The detailed shot in test 5, which showed a low saturation level, also resulted in poor visibility with HRDCP and NGCCLAHE compared to the proposed method. WSDACC showed considerably insufficient visibility in distant scenes, similar to Figure 10, due to the dark background color and poor dehazing performance. The proposed method preserved the hue of the distance scenes in all detailed shots and showed superb visibility improvement. The proposed method showed the most natural and highest contrast. Figure 10: Color-restored dehazing results of general hazy images: (**a**) original hazy image, (**b**) HRDCP, (**c**) NGCCLAHE, (**d**) WSDACC, and (**e**) proposed dehazing method. The results in Table 1 show that the proposed method exhibited lower values for \(\overline{r}\), which represents the contrast between the background and the object, compared to HRDCP and NGCCLAHE. However, visually, it produced the sharpest images in the \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **Image** & **HRDCP** & **NGCCLAHE** & **WSDACC** & **Proposed** \\ \hline \multirow{4}{*}{e} & Test 1 & 0.0488 & 0.0738 & 0.0669 & 0.1049 \\  & Test 2 & 0.1016 & 0.1186 & \(-\)0.1143 & 0.1220 \\  & Test 3 & 0.4725 & 0.3975 & 0.0997 & 0.5101 \\  & Test 4 & 0.0583 & 0.0864 & \(-\)0.0107 & 0.0723 \\  & Test 5 & 0.4270 & 0.3816 & 0.0155 & 0.3979 \\  & **Average** & **0.2217** & **0.2116** & **0.0114** & **0.2415** \\ \hline \multirow{4}{*}{\(\overline{r}\)} & Test 1 & 2.2533 & 1.7719 & 0.4047 & 1.3618 \\  & Test 2 & 2.9243 & 2.1153 & 1.6180 & 1.3698 \\  & Test 3 & 2.2332 & 1.7682 & 0.9952 & 1.5707 \\  & Test 4 & 2.4951 & 1.9173 & 1.0384 & 1.3632 \\  & Test 5 & 2.7109 & 1.9456 & 0.7972 & 1.6737 \\  & **Average** & **2.5233** & **1.9036** & **0.9707** & **1.4678** \\ \hline \multirow{4}{*}{FRF} & Test 1 & 0.3485 & 0.4788 & \(-\)0.0226 & 0.4585 \\  & Test 2 & 0.0888 & 0.1256 & \(-\)0.2988 & 0.1285 \\  & Test 3 & 0.0783 & 0.0237 & 0.0349 & 0.1731 \\  & Test 4 & 0.3383 & 0.3456 & \(-\)0.0530 & 0.3544 \\  & Test 5 & 0.5303 & 0.4742 & \(-\)0.0401 & 0.5797 \\  & **Average** & **0.2768** & **0.2896** & \(-\)**0.0759** & **0.3388** \\ \hline \multirow{4}{*}{PIQE} & Test 1 & 44.4367 & 46.4053 & 50.2147 & 40.1527 \\  & Test 2 & 40.0996 & 35.7676 & 31.8466 & 29.2613 \\ \cline{1-1}  & Test 3 & 43.7708 & 42.1776 & 35.8692 & 40.3450 \\ \cline{1-1}  & Test 4 & 44.0385 & 42.1096 & 42.0236 & 36.5857 \\ \cline{1-1}  & Test 5 & 26.1658 & 30.8974 & 38.2872 & 25.0304 \\ \cline{1-1}  & **Average** & **39.7023** & **39.4715** & **39.6483** & **34.2750** \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Visual quality assessment results for a typical fog image. Figure 11: Color restoration dehazing results of general hazy images: (**a**) original hazy image, (**b**) HRDCP, (**c**) NGCCLAHE, (**d**) WSDACC, and (**e**) proposed dehazing method. results, as shown in Figures 10 and 11, and had the best visual quality for e, FRF, and PIQE, with the exception of \(\overline{r}\). In particular, the proposed method showed remarkably high results in the fog concentration difference FRF and quality score PIQE, indicating strong defogging performance.