Number Plate Recognition in Home Assistant

I found a great Idea online to set up number plate recognition in home assistant. I thought I would write it down partially because Australia has number plates starting with a number which caused me issues with a sensor.

First thing first, Most information, including the idea, came from the youtube video found here https://www.youtube.com/watch?v=t-XxCrdj_94, and you can find more great ideas at https://everythingsmarthome.co.uk/

What you will need:

1. A free account with https://platerecognizer.com/
2. The plate Recognizer add-on found at https://github.com/robmarkcole/HASS-plate-recognizer
3. HACS for Home Assistant

Install HASS-plate-recognizer

Open the HACS Store.

1. Click on the three dots on the top right
2. Click on custom repositories

3. Add the custom repository https://github.com/robmarkcole/HASS-plate-recognizer
4. Select Integration as the category and click add.
5. Open the now-added plugin repository and install
6. Once Installed, you will now need to restart Home Assistant for the add-on to activate.

Configuration

I am detecting my wife and my number plate using a Reolink camera. As I do not want to use all my free credit for platerocgnizer.com I have an automation to only activate the camera on motion.

configuration.yaml

#Number Plate Recognition
image_processing:
  - platform: platerecognizer
    api_token: !secret plate_recognizer_api
    regions:
      - au-wa #platerecognizer region code
    watched_plates:
      - 1xxxxx # number Plate
      - 1xxxxx #number plate
    save_file_folder: /config/www/plates
    save_timestamped_file: True
    always_save_latest_file: True
    mmc: True
    source:
      - entity_id: camera.garage_sub

sensor.yaml

I put my sensors in a separate yaml file and it is defined in my configurations.yaml file

- platform: template
  sensors:
    plate_recognizer:
      friendly_name: "David's Car 1xxxxx"
      value_template: "{{ state_attr('image_processing.platerecognizer_garage_sub', 'watched_plates')['1xxxx']  }}"
      unique_id: 'sensor.car_1xxxxxx'
    plate_recognizer_3:
      friendly_name: "Wife's Car 1xxxxx"
      value_template: "{{ state_attr('image_processing.platerecognizer_garage_sub', 'watched_plates')['xxxxx']  }}"
      unique_id: 'sensor.car_1xxxx'

You will notice in the git that the value template is different from the watched template. When I was using the number 1 for the license plate, it was not working, and after some research, I had to change the way it was written.

automation config

You will notice I have a delay and run the action again. this is to change the license plate from true to false if it is no longer detected.

alias: "Number plate recognition "
description: ""
trigger:
  - platform: state
    entity_id:
      - binary_sensor.garage_cam_motion
    to: "on"
condition: []
action:
  - service: image_processing.scan
    data: {}
    target:
      entity_id: image_processing.platerecognizer_garage_sub
  - delay:
      hours: 0
      minutes: 5
      seconds: 0
      milliseconds: 0
  - service: image_processing.scan
    data: {}
    target:
      entity_id: image_processing.platerecognizer_garage_sub
mode: single

Second Automation

Finally, I have a second automation to trigger the garage to open if the number plate is recognised. I have a notification currently enabled for testing.

alias: Vehicle Detected
description: ""
trigger:
  - platform: state
    entity_id:
      - sensor.plate_recognizer_2
    from: "False"
    to: "True"
condition: []
action:
  - type: toggle
    device_id: e8f4a030bb004e97b96a1c47cb4a4469
    entity_id: switch.garage_control
    domain: switch
    enabled: true
  - service: notify.mobile_app_pixel_7_pro
    data:
      title: License Plate Detection
      message: License Plate Detection
      data:
        image: /local/plates/platerecognizer_garage_sub_latest.png
        attachment:
          url: /local/plates/platerecognizer_garage_sub_latest.png
          content-type: jpg
          hide-thumbnail: false
mode: single

I hope this helps others with their configuration.