How can I acquire [Artery] and [Vein] labels from the data I generate from docker?

[liang-fen]

I have generated some vessel data according to your instructions. The structure is as follows:

C:.
├─images
│ generator_20240920_091544_039d6383-5981-4049-bc4f-f292020f3086.png
│
├─labels
│ 20240920_091544_039d6383-5981-4049-bc4f-f292020f3086_label.png
│
└─vessel_graphs
├─20240920_091544_039d6383-5981-4049-bc4f-f292020f3086
│ 20240920_091544_039d6383-5981-4049-bc4f-f292020f3086.csv
│ art_ven_img_gray.png
│ config.yml

How can I extract information about [Artery] and [Vein] labels.
I find the img under [labels] dir only has one gray value suggesting it's only label for vessels.
The img under [vessel_graghs] has so much values that seems like a non-background octa img rather than a label img.
Is the data in csv file under [vessel_graghs] dir suggests the differnce between artery and vein? I know the node data in it has 3 dimentions but don't know what it means.