ANPR questions & answers
Answers for the systems around number-plate recognition.
Practical, vendor-neutral guidance for cameras, NVRs, VMS platforms, access control and metadata integrations.
These are general industry answers, not product support. Setting up ANPR Edge? Read the camera connection guide.
5 answerin NVR
Why does my Hikvision ANPR camera show video on a third-party NVR, but no license plates?
Video feeds and ANPR metadata are transmitted using completely different network protocols. While your third-party NVR can receive the standard video feed via ONVIF Profile S or RTSP, Hikvision transmits its license plate text and vehicle metadata using proprietary ISAPI or ISUP payloads that non-Hikvision NVRs cannot decode.
Hikvision ISAPI Event Notification Integration
Can a Uniview (UNV) NVR perform Smart Plate Search with a third-party ANPR camera?
No. Uniview explicitly locks its advanced metadata analytics, including Plate Comparison and Smart Vehicle Search, to its own Uniview-branded LPR cameras. Third-party cameras can only provide basic, unsearchable video streams to the UNV NVR.
Uniview NVR516-64E Datasheet Specifications
Why does Avigilon LPR Performance Mode disable Face Recognition on AI NVRs?
Activating high-performance LPR heavily taxes the AI NVR's computational resources. To prevent frame dropping and maintain accurate plate reads on fast-moving vehicles, the system redirects all available processing power to the OCR engine, intentionally disabling conflicting analytics like Face Recognition.
Avigilon Unity Video - Setting up License Plate Recognition
Why are Wisenet WAVE LPR bookmarks playing back at the wrong time?
If clicking an LPR event bookmark in the Wisenet WAVE client jumps the video playback to a timestamp completely devoid of a vehicle, you are experiencing a severe clock synchronization mismatch. The VMS server and the edge cameras are operating on different clocks.
Hanwha Vision: Synch issue between playback time and camera time
Can ONVIF Profile S send ANPR metadata?
No. There is a universal misunderstanding across the industry that ONVIF Profile S supports metadata. Profile S only standardizes the transmission of RTSP video pixels and simple binary motion alarms. It cannot transmit license plate text or structured XML metadata.
ONVIF Profile M Overview and Specifications
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