Viewtron LPR Camera API / HTTP Post Integration Questions

Home › Forums › Viewtron Security Camera Systems Support › License Plate Recognition (LPR) › Viewtron LPR Camera API / HTTP Post Integration Questions

  • A customer contacted us with the following questions about our Viewtron LPR cameras. I’m evaluating 2x Viewtron LPR-IP4 cameras for an entry/exit license-plate deployment and need to confirm a few integration details before purchasing. The cameras would feed a custom cloud backend, so I’m trying to determine the exact hardware I need.
    1. Direct event POST without an NVR. Can the LPR-IP4 POST its ANPR/plate-read events (license plate text, confidence, capture timestamp, and a snapshot image or image URL) directly to an external HTTPS endpoint via HTTP POST / webhook — with NO NVR or VMS required in the path? If yes, what is the exact payload format (XML or JSON) and can I configure the destination URL and headers in the camera’s web UI?Yes. The Viewtron LPR-IP4 can send an HTTP Post to an endpoint URL that you specify. It can do this with or without using a Viewtron NVR. You can find the HTTP Post and LPR detection setup instructions here. https://videos.cctvcamerapros.com/v/lpr-camera-api.htmlThe payload that the Post sends is XML. You can see the raw XML payload as well as Python and Node SDK examples here.
      https://videos.cctvcamerapros.com/developer/docs/applications/license-plate-recognition-camera-api
    2. If an NVR IS required. If the camera cannot emit events standalone and needs an NVR (or VMS) to forward ANPR events, please confirm that, and tell me which NVR model is required and whether that NVR can forward plate events to an external HTTPS endpoint.The NVR is not required, but for most customers, it makes managing the LPR camera easier because the NVR’s UI is fully integrated with setting up and managing all licence plate recognition functions. For a developer that wants to use the API, you do not need the NVR unless you want to use it as your storage for recordings.
    3. Payload contents. For each plate read, does the event include: plate number, confidence score, direction or lane ID, timestamp, and an image (attached or as a URL)? A sample event payload would be extremely helpful.There is no confidence score and no direction attributes. License plate number, timestamp, image, and copped plate image are all included in the XML payload. You can find the entire sample post here. https://videos.cctvcamerapros.com/developer/docs/applications/license-plate-recognition-camera-api
    4. Software-triggered gate/door output. Can the camera (or its API) trigger a relay / dry-contact output, or accept an API command, to open a gate or door based on a software decision from my backend? If so, is that an on-camera relay or does it require additional hardware?Yes. The Viewton LPR-IP4 has a built-in dry contact relay. The relay can be triggered based on the built-in automatic license plate recognition / license plate database. You can also manually trigger the relay output via an API call from your software.
    5. Network requirements. Does the camera need any inbound ports open, or does it only make outbound HTTPS connections? (Outbound-only is strongly preferred for my deployment.)No internet connection or reliance on a cloud service. All of the license plate detection and automatic license plate recognition inference software runs locally on the LPR camera itself.
    6. Current pricing and lead time for 2x LPR-IP4, plus any required NVR or accessories based on your answers above.Current pricing for the LPR-IP4 is $699.99 each. The only accessories you need are a PoE switch or PoE injectors, and network cable. These PoE injectors work. https://www.cctvcamerapros.com/POE-Injector-Kit-p/poe-12v48.htmThis PoE switch works.
      https://www.cctvcamerapros.com/IP-Camera-PoE-Switch-p/poe-sw54.htm
    If you have any additional questions about license plate recognition software development with Viewtron LPR cameras, you can email mike@viewtron.com.