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License Plate Recognition Service

The ALPR (Automatic License Plate Recognition) Service allows users to control ALPR engines and ALPR database for license plate detection and recognition tasks

To access the service, go to APLR Service in the Setting page.

ALPR database​

With the ALPR service, you can filter detection based on registered plates, unregistered plates, or group membership. This means instead of detecting every visible plate, ANSVIS tasks can now focus on specific scenarios — such as parking systems, restricted areas, or monitoring VIP/blacklisted vehicles.

Adding license plates​

You can register license plates in two ways:

  • Manual Entry: Press the Add button to manually register a plate number into the system
  • Import from CSV: Press the Import from CSV file to upload a CSV file containing a list of license plates for bulk registration following ANS format (click the i icon to learn more).

Creating and managing license groups​

  • Press the Edit Groups button to start creating and managing groups (e.g., Employees, Visitors, Blacklisted, VIP)
  • After creating groups, you can now assign the license plates to one or more groups.
  • Edit or remove groups anytime to match your operational needs.

Filtering options​

When configuring an ALPR task, you can filter detected results by:

  • All License Plates: Detect every visible license plate.
  • Registered Only: Detect only plates in your database.
  • Unregistered Only: Detect plates not in your database.
  • Group Filters: Include or exclude specific groups (e.g., detect only Blacklisted vehicles).

ALPR Engine Options​

Currently support Vietnamese ALPR

  • Detector Min Score: Set the confidence level for plate detection. A lower value may detect more plates but may include false positives.
  • OCR Min Score: Set the confidence level required for the OCR engine to confirm a recognized character. Higher values ensure greater accuracy but might miss unclear plates.
  • Color Min Score: Set the confidence level for plate color detection. A lower value may detect may detect colors with lower confidence. Set to 0 if you want to disable this function. To see color detection in event log, enable the Extra info option
caution

The engine setting will be applied to all APLR tasks