Impossible to process image from clipboard or take screenshot of desktop.

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:bust_in_silhouette: Asked By Myrmex

Hello. I made an app that analyzes imported fragment from another app, performs some measurements and saves it to the log. The whole process is quite bothersome at the moment as it requires user to save a screenshot on the disk, open it in explorer, drag&drop onto my program and then delete that image. Every time.
I was thinking of any way to ease this part by using screencap software to save a fragment in the clipboard and grab it from there, but the only related method OS.get_clipboard() doesn’t work with anything but strings.
Another thought was to make a desktop screenshot from the app itself via hotkey and manually select a region to work with but I could hardly find any discussion on this topic and it seems that such functionality isn’t even present in godot for reasons.

Is there any other way to process system’s screen region without saving it as image file? Any side libraries?