Ah, I thought you were looking to get a real-world camera. My apologizes!
As for getting the image from a Godot camera, it depends on whether you are wanting to get images from multiple cameras or just a single camera (per Godot application).
To get the image from a single camera, you can use get_tree().root.get_texture().get_data() will return a static image. There is a demo on the Godot demo repository that might be helpful to look at. If you want an updating texture, which may or may not be compatible with TensorFlow, you can remove get_data() from the function to get a ViewportTexture (documentation), which will update as the Viewport renders.
If you want to get multiple camera textures, then you will need to have each Camera as a child of a Viewport node, where the Viewport node has the resolution you want (by default viewports are set to (0, 0), which will not produce an image). If you want both cameras to view the same scene, you need to make sure that own world is disabled, otherwise the camera will only see nodes that are children of the Viewport node.
Then the code for accessing the image from each viewport can be achieved with the following (untested):
extends Spatial
var viewport_one
var viewport_two
func _ready():
# Get the viewports
viewport_one = get_node("path_to_viewport_one")
viewport_two = get_node("path_to_viewport_two")
func _process(_delta):
var image_one = viewport_one.get_texture().get_data()
var image_two = viewport_two.get_texture().get_data()
Then from there you should have access to the both images from both cameras. From there you'll have to find a way to pass the image to TensorFlow, which I'm not sure how that would work.
