# Illuminant Adaptive Wideband Image Synthesis Using Separated Base-Detail Layer Fusion Maps
## 4 Simulation Results
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Half Mixed** & **Low Rank** & **Dense Fusion** & **Vanmali** & **PCA Fusion** & **Proposed** \\ \hline
1 & 12.54686 & 14.14278 & 13.94147 & 15.9371 & 19.472 & 24.33865 \\
2 & 12.4484 & 15.05581 & 12.68151 & 16.60634 & 17.24116 & 23.4287 \\
3 & 17.34853 & 20.25724 & 18.68782 & 21.34845 & 26.16536 & 36.68218 \\
4 & 10.14903 & 11.66165 & 10.66109 & 13.74866 & 19.43001 & 21.46389 \\
5 & 7.238538 & 9.097301 & 8.040366 & 10.16365 & 18.85362 & 13.88883 \\
6 & 20.75647 & 24.89999 & 20.74539 & 23.60679 & 21.74731 & 38.34033 \\
7 & 16.09507 & 19.39597 & 15.99705 & 20.85826 & 18.50416 & 25.57275 \\
8 & 13.67963 & 17.51154 & 13.48037 & 15.63094 & 16.24731 & 20.72835 \\
9 & 12.45933 & 15.2962 & 12.35908 & 14.98069 & 14.40758 & 18.1312_Appl. Sci._**2022**, _12_, 9441 \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & **Half Mixed** & **Low Rank** & **Dense Fusion** & **Vanmali** & **PCA Fusion** & **Proposed** \\ \hline
1 & 3.880816 & 4.153757 & 4.299817 & 5.010667 & 6.093581 & 7.418859 \\
2 & 4.516674 & 5.255388 & 4.598725 & 5.873233 & 6.03323 & 8.274568 \\
3 & 6.478177 & 7.300047 & 6.966816 & 7.961987 & 9.733417 & 13.46038 \\
4 & 3.322676 & 3.596682 & 3.48355 & 4.629657 & 6.418822 & 6.852565 \\
5 & 2.4430345 & 2.811208 & 2.712147 & 3.256926 & 5.96494 & 4.229757 \\
6 & 7.359794 & 8.171345 & 7.356862 & 8.552003 & 7.804351 & 13.56777 \\
7 & 4.66935 & 5.926646 & 4.645744 & 6.104861 & 5.591356 & 6.992199 \\
8 & 4.355526 & 5.472404 & 4.293732 & 5.063539 & 5.076561 & 6.208429 \\
9 & 4.132718 & 5.207001 & 4.098049 & 5.251618 & 4.762244 & 5.555363 \\
10 & 3.414311 & 4.782535 & 3.362169 & 4.379015 & 5.719537 & 5.342915 \\
11 & 2.798207 & 4.212974 & 2.785703 & 4.854306 & 4.732941 & 4.743542 \\
12 & 2.377223 & 4.019897 & 2.387551 & 4.012972 & 5.201723 & 3.872744 \\
13 & 3.028285 & 5.025304 & 2.978305 & 4.864133 & 5.689062 & 5.233637 \\ \hline Average & 4.059754 & 5.071938 & 4.151475 & 5.370381 & 6.063213 & 7.062765 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Comparison of the average gradient metrics. Figure 20: Metric scores: (**a**) S3 score; (**b**) VIFF score; (**c**) spatial frequency score (**d**) LPC SI score; (**e**) edge intensity score; (**f**) average gradient score. Spectral and spatial sharpness (S3) generates a sharpness map considering human cognitive characteristics, and a larger local value indicates a visually sharper area. This is used to evaluate the quality and sharpness of the images in general [15]. Visual information fidelity for fusion (VIFF) is a quality metric that measures the effective visual information of fusion in all blocks in each sub-band. This is obtained by using the VIF models to gather visual information from the source and fused image pair [16]. Spatial frequency (SF) is used to observe the distribution of gradients throughout the image by calculating vertical and horizontal gradients and to evaluate the amount of detail and texture that can be perceived by humans [17]. LPC-SI is an image sharpness evaluation index that uses the fact that strong local phase coherence occurs in objects or regions that visually stand out in the complex wavelet transform domain [18]. Edge intensity (EI) is an image evaluation method based on the idea that high edge intensity values are superior in terms of image quality and sharpness [19]. The average gradient (AG) metric quantifies the gradient information in the fused image and reveals the details and textures [20]. Regarding the evaluation indicators S3, VIFF, SF, LPC-SI, EI, and AG used in this evaluation, the higher the performance evaluation value, the better the performance in terms of image quality and sharpness. The proposed synthesis method shows, on average, fine improvements of 1.48% for S3, 11.47% for VIFF, 15.49% for SF, 0.92% for LPC-SI, 16.77% for EI, and 14.15% for AG, compared to the method with the highest performance among the existing methods.