## 4 Experiments and Analysis
### Experimental Results and Analysis
\begin{table}
\begin{tabular}{c c c c c c} \hline  & **CC (1)** & ERGAS (0)** & **SID (0)** & **RASE (0)** & **QNR (1)** \\ \hline BL & 0.442 & 6.683 & 0.050 & 28.734 & 0.584 \\ AGS & 0.313 & 7.504 & 0.065 & 26.254 & 0.351 \\ GFD & 0.757 & 5.611 & 0.021 & 20.598 & 0.568 \\ IHST & 0.464 & 6.129 & 0.029 & 26.129 & 0.597 \\ MOD & 0.943 & 1.604 & 0.007 & 5.147 & 0.903 \\ MPCA & 0.473 & 6.240 & 0.049 & 26.640 & 0.558 \\ PRACS & 0.943 & 1.606 & 0.009 & 5.174 & 0.816 \\ VLGC & 0.944 & 1.601 & 0.008 & 5.157 & 0.901 \\ BDSD-PC & 0.942 & 1.611 & 0.007 & 5.159 & 0.884 \\ WTSR & 0.733 & 3.053 & 0.021 & 11.237 & 0.573 \\ Proposed & 0.947 & 1.488 & 0.005 & 4.956 & 0.925 \\ \hline \end{tabular}
\end{table} 
Table 4: The fourth group of quantitative results. \begin{table}
\begin{tabular}{c c c c c c} \hline  & **CC (1)** & ERGAS (0)** & **SID (0)** & **RASE (0)** & **QNR (1)** \\ \hline BL & 0.721 & 5.093 & 0.010 & 23.304 & 0.495 \\ AGS & 0.491 & 5.986 & 0.018 & 28.299 & 0.316 \\ GFD & 0.768 & 5.614 & 0.015 & 22.543 & 0.676 \\ IHST & 0.735 & 5.509 & 0.009 & 21.980 & 0.550 \\ MOD & 0.949 & 1.765 & 0.002 & 7.202 & 0.894 \\ MPCA & 0.592 & 5.120 & 0.010 & 20.987 & 0.504 \\ PRACS & 0.930 & 1.860 & 0.003 & 7.566 & 0.780 \\ VLGC & 0.952 & 1.730 & 0.002 & 7.124 & 0.956 \\ BDSD-PC & 0.949 & 1.765 & 0.002 & 7.200 & 0.884 \\ WTSR & 0.869 & 2.764 & 0.006 & 11.273 & 0.567 \\ Proposed & 0.950 & 1.488 & 0.001 & 4.956 & 0.984 \\ \hline \end{tabular}
\end{table} 
Table 2: The second group of quantitative results. \begin{table}
\begin{tabular}{c c c c c c} \hline  & **CC (1)** & ERGAS (0)** & **SID (0)** & **RASE (0)** & **QNR (1)** \\ \hline BL & 0.796 & 2.658 & 0.010 & 8.092 & 0.548 \\ AGS & 0.793 & 3.697 & 0.016 & 9.058 & 0.435 \\ GFD & 0.845 & 2.157 & 0.015 & 7.627 & 0.648 \\ IHST & 0.731 & 1.674 & 0.009 & 6.741 & 0.515 \\ MOD & 0.913 & 1.106 & 0.002 & 4.595 & 0.894 \\ MPCA & 0.798 & 1.851 & 0.017 & 7.707 & 0.535 \\ PRACS & 0.887 & 1.233 & 0.019 & 5.068 & 0.851 \\ VLGC & 0.912 & 1.120 & 0.003 & 4.651 & 0.909 \\ BDSD-PC & 0.911 & 1.106 & 0.006 & 4.595 & 0.884 \\ WTSR & 0.836 & 1.448 & 0.013 & 5.966 & 0.640 \\ Proposed & 0.914 & 1.488 & 0.001 & 4.956 & 0.946 \\ \hline \end{tabular}
\end{table} 
Table 3: The third group of quantitative results. value on the SID index and the third best values on the CC and RASE indices. Thus, from the perspective of objective evaluation in Table 1, the proposed method has superior spatial detail retention characteristics and spectral retention characteristics, and the overall effect is better. In Figure 10, compared with the reference MS image, the BL, AGS, IHST, and MPCA methods appear spectral distortion with different degrees in the overall region. Especially, in the local magnification region, for the BL method, the dark green part becomes dark blue. For the AGS and MPCA methods, the dark green part becomes yellowish. For the IHS method, the dark green part becomes light green. Moreover, the WTSR and GFD methods have severe spatial detail distortion. The fused images obtained by the MOD, PRACS, VLGC, and BDSD-PC methods have a higher spectral resolution and retain the spectral information contained in the MS images. However, compared with these methods, the spatial details of the proposed method are more defined, especially in the local magnification region. In Figure 8, from the analysis of subjective vision, the proposed method has clearer spatial details and higher spectral resolution, which means that the proposed method improves spatial details while more spectral information contained in the MS images is retained. In Table 2, the proposed method can obtain the best values on all six quantitative indices. In particular, the QNR value of the proposed method is 0.984, which is relatively close to the optimal value of 1. In addition, the VLGC method can obtain the second best values on all six indices. The MOD method can obtain the second best value on the SID index and the third best values on the CC, ERGAS and QNR indices.