LogoLogo
Buy SoftwareBuy HardwareOpen a ticket
Developer Ecosystem
Developer Ecosystem
  • 🚘Rekor CarCheck®
    • Rekor CarCheck® Overview
    • Countries and Regions Supported
    • Vehicle Characteristics Supported
    • Create an Account
    • Integration
    • Code Samples
    • Web Dashboard
  • ⚙️Vehicle Recognition SDK
    • Vehicle Recognition SDK Overview
    • Countries and Regions Supported
    • Vehicle Characteristics Supported
    • Request a License
    • Installation
      • Windows
      • Ubuntu Linux
    • Vehicle Recognition Image API
      • C++
      • C
      • Samples
    • Vehicle Recognition Stream API
      • C++
      • C
      • Samples
Powered by GitBook
LogoLogo

Platforms

  • Rekor Discover® for Urban Mobility
  • Rekor Command® for Transportation
  • Rekor Scout® for Public Safety

Systems

  • Rekor Edge Flex™ (Classificaiton)
  • Rekor Edge Max™ (Classification)
  • Rekor Edge Pro (ALPR)
  • Rekor Edge Max™ (ALPR)

Developers

  • Vehicle Recognition SDK
  • Rekor CarCheck®
  • Rekor AutoNotice™

Resources

  • About Us
  • Customer Stories
  • Newsroom
  • Help Center

© 2025 Rekor Systems, Inc. All Rights Reserved.

On this page
  • Download
  • Licensing
  • Command Line Utility
  • Detailed Command Line Usage

Was this helpful?

  1. Vehicle Recognition SDK
  2. Installation

Ubuntu Linux

PreviousWindowsNextVehicle Recognition Image API

Last updated 1 year ago

Was this helpful?

Download

The Linux Vehicle Recognition SDK is available in the commercial APT repository.

The libopenalpr-dev package will install the necessary headers and library packages into your system. To install, run:

bash <(curl -s https://deb.openalpr.com/install)

Select install_sdk from the menu.

You must be on Ubuntu version 18.04 or above.

Licensing

Before running the software you must obtain a license key. If you haven't already done so, please visit the section to submit your information.

After acquiring a license, paste the license key into the license.conf file to begin using the software. Alternatively, you can set the license as an environment variable named OPENALPR_LICENSE_KEY.

Command Line Utility

The Vehicle Recognition SDK includes a command line utility. Simply type alpr [image file path] to get started with recognizing license plate images.

For example, the following output is created by analyzing this image:

user@linux:~/openalpr$ alpr ./samplecar.png

plate0: top 10 results -- Processing Time = 58.1879ms.
    - LTM378     confidence: 88.9371
    - LTM37B     confidence: 78.1385
    - LTM37      confidence: 77.5444
    - 1TM378     confidence: 76.1448
    - 1TM37B     confidence: 72.9016
    - LTME78     confidence: 72.1147
    - TM37       confidence: 66.7458
    - LTME7B     confidence: 65.3462
    - 1TME7B     confidence: 62.1031
    - 1TM37B     confidence: 61.5089

Detailed Command Line Usage

user@linux:~/openalpr$ alpr --help

USAGE: 

   alpr  [-c <country_code>] [--config <config_file>] [-n <topN>] [--seek
         <integer_ms>] [-p <pattern code>] [--clock] [-d] [-j] [--]
         [--version] [-h] <image_file_path>


Where: 

   -c <country_code>,  --country <country_code>
     Country code to identify (either us for USA or eu for Europe). 
     Default=us

   --config <config_file>
     Path to the openalpr.conf file

   -n <topN>,  --topn <topN>
     Max number of possible plate numbers to return.  Default=10

   --seek <integer_ms>
     Seek to the specified millisecond in a video file. Default=0

   -p <pattern code>,  --pattern <pattern code>
     Attempt to match the plate number against a plate pattern (e.g., md
     for Maryland, ca for California)

   --clock
     Measure/print the total time to process image and all plates. 
     Default=off

   -d,  --detect_region
     Attempt to detect the region of the plate image.  [Experimental] 
     Default=off

   -j,  --json
     Output recognition results in JSON format.  Default=off

   --,  --ignore_rest
     Ignores the rest of the labeled arguments following this flag.

   --version
     Displays version information and exits.

   -h,  --help
     Displays usage information and exits.

   <image_file_path>
     Image containing license plates
⚙️
Request a License
Rekor Scout®
BMW with a Texas license plate