Geometry comes before artificial intelligence
Recognition software cannot reconstruct a plate that occupies too few pixels, is hidden by glare, or crosses the view at an extreme angle. The lane, stopping point, vehicle direction, speed, mounting surface, focal length, and night exposure must be designed together.
For the UniFi AI-LPR, Ubiquiti recommends a capture distance within 12 meters, mounting below 5 meters, and horizontal and vertical angles below 25 degrees. Faster traffic calls for angles below 15 degrees. Slower or stopped vehicles may allow modestly longer distances and angles, but field testing decides the result.
- Keep the plate large in the frame
- Minimize horizontal and vertical angle
- Control where the vehicle slows or stops
- Audit both front and rear plate opportunities
Why the LPR needs a context camera
At night, a dedicated plate camera may expose for reflective material and suppress the rest of the scene. That is excellent for characters and poor for understanding occupants, vehicle color, damage, direction, or activity around the gate.
A second overview camera provides the story around the plate event. In Protect, operators can review the plate detection alongside broader video instead of asking one exposure and field of view to do incompatible jobs.
- LPR camera: identification evidence
- Overview camera: vehicle and scene context
- Entry camera: driver or visitor interaction
- Recorder: retention and event correlation
From plate logging to gate access
Compatible Protect AI cameras can pass recognized authorized plates into UniFi Access when paired with a Gate Hub deployment. That convenience changes the risk profile: detection zones, credentials, cooldown behavior, event recording, software versions, and operator safety interfaces all need deliberate commissioning.
The access platform should never bypass the gate operator's safety system. Entrapment protection, loops, photo eyes, emergency behavior, and applicable requirements remain part of the gate installation even when the credential is a license plate.
- Assign plates to named users
- Limit the detection and unlock zone
- Record video on access events
- Test rejected, unreadable and repeated approaches