Reading qrcode (non-unique) once per session with Arkit+Vision

Question

Given two QRcode (not unique) fixed in space. As with Arkit and Vision, count each code once per session, even if we take away the camera.

I managed to write reading QRcodes into a session (hitTest) and using Vision to recognize and add a 3D object, but how to read two (or more) identical barcodes on the screen once (even if we remove the camera and return the QRcodes to the same)? Can remember them coordinates?

Please tell me please