home-assistant.io/source/_components/seven_segments.markdown

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title	description	logo	ha_category	ha_release	og_image	ha_iot_class	redirect_from
Seven segments display	Instructions on how to use OCR for seven segments displays into Home Assistant.	home-assistant.png	Image Processing	0.45	/images/screenshots/ssocr.png	Local Polling	/components/image_processing.seven_segments/

The seven_segments image processing platform allows you to read physical seven segments displays through Home Assistant. ssocr is used to extract the value shown on the display which is observed by a camera.

If you are using Hass.io then just move forward to the configuration as all requirements are already fulfilled.

ssocr needs to be available on your system. Check the installation instruction below:

$ sudo dnf -y install imlib2-devel # Fedora
$ sudo apt install libimlib2-dev # Ubuntu
$ brew install imlib2 # macOS
$ git clone https://github.com/auerswal/ssocr.git
$ cd ssocr
$ make
$ sudo make PREFIX=/usr install # On most systems
$ make deb # (Optional) This allows you to make a deb so that you apt is aware of ssocr

To enable the OCR of a seven segment display in your installation, add the following to your configuration.yaml file:

# Example configuration.yaml entry
image_processing:
  - platform: seven_segments
    source:
      - entity_id: camera.seven_segments

{% configuration %} ssocr_bin: description: The command line tool ssocr. Set it if you use a different name for the executable. required: false default: ssocr type: string x_position: description: X coordinate of the upper left corner of the area to crop. required: false default: 0 type: integer y_position: description: Y coordinate of the upper left corner of the area to crop. required: false default: 0 type: integer height: description: Height of the area to crop. required: false default: 0 type: integer width: description: Width of the area to crop. required: false default: 0 type: integer rotate: description: Rotation of the image. required: false default: 0 type: integer threshold: description: Threshold for the difference between the digits and the background. required: false default: 0 type: integer digits: description: Number of digits in the display. required: false default: -1 type: integer extra_arguments: description: Other arguments to use. Like -D, dilation, erosion, greyscale, make_mono, etc. required: false type: string source: description: List of image sources. required: true type: list keys: entity_id: description: A camera entity id to get picture from. required: true type: string name: description: This parameter allows you to override the name of your image_processing entity. required: false type: string {% endconfiguration %}

Setup process

It's suggested that the first attempt to determine the needed parameters is using ssocr directly. This may require a couple of iterations to get the result

$ ssocr -D erosion crop 390 250 490 280 -t 20 -d 4 seven-seg.png

This would lead to the following entry for the configuration.yaml file:

camera:
  - platform: local_file
    file_path: /home/homeassistant/.homeassistant/seven-seg.png
    name: seven_segments
image_processing:
  - platform: seven_segments
    x_position: 390
    y_position: 250
    height: 280
    width: 490
    threshold: 20
    digits: 4
    source:
      - entity_id: camera.seven_segments

With the help of a template sensor, the value can be shown as badge.

{% raw %}

sensor:
  - platform: template
    sensors:
      power_meter:
        value_template: '{{ states('image_processing.sevensegment_ocr_seven_segments') }}'
        friendly_name: 'Ampere'
        unit_of_measurement: 'A'

{% endraw %}