*3.3. Visual Comparison*

In this work, the first three reflection channels of AGRI (CH01, CH02, and CH03) are used for visible light spectrum combination. The combined images of the three RGB channels are more in line with the human eye observation and can effectively visualize the details of oceans, lands, and clouds. Meanwhile, the long-wave infrared band CH11 is used, and its main visual content is water vapor and cloud features. Due to the lack of features of the underlying surface of the earth in the visual results of CH11, the image translation from the infrared spectral domain to the visible spectral domain poses a challenge to the model.

Figures 3–5 illustrate two examples of the translation between the above two sets of spectral remote sensing images. Each set contains image information such as oceans, lands, and clouds. In Figure 3, the underlying surface of the earth in group (a) is mainly land, and that of the earth in group (b) is dominated by the ocean. Figure 4 shows the visual comparison of different models for translation from infrared spectrum domain to visible spectrum domain. Figure 5 shows the visual comparison of different models for translation from visible spectrum domain to infrared spectrum domain.

**Figure 3.** *Cont*.

Surface Type Label 

Cloud Type Label 

Ground Truth Visible Image

SDTGAN

with

Surface

Label

**Figure 3.** The input spectral-domain images and condition information of the two sets of visual comparison experiments. The first line presents label maps of the earth surface type; the second line presents cloud-type label maps; the third line presents the ground-truth of the infrared remote sensing image; and the fourth line presents the ground-truth of the visible remote sensing image. Subfigures (**a**) and subfigures (**b**) are two independent test cases.

**Figure 4.** *Cont*.

SDTGAN with Surface and Cloud Label 

> Pix2pix-HD

> > Cycle-GAN

**Figure 4.** *Cont*. UNIT

**Figure 4.** Visual comparison of different models for translation from infrared spectrum domain to visible spectrum domain. Subfigures (**a**) and subfigures (**b**) are two independent test cases.

SDTGAN with Surface Label

SDTGAN with Surface and Cloud Label 

**Figure 5.** *Cont*.

Pix2pix-HD 

Cycle-GAN

UNIT
