Description:

Related issue (if applicable): fixes #7954

Pull request in home-assistant.github.io with documentation (if applicable): home-assistant/home-assistant.io#2802

Example entry for configuration.yaml (if applicable):

image_processing:
  - platform: seven_segments
    x_position: 390
    y_position: 250
    height: 280
    width: 490
    rotate: 3
    threshold: 20
    digits: 4
    extra_arguments: "-D erosion"
    source:
      - entity_id: camera.seven_segments

Checklist:

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in home-assistant.github.io

If the code communicates with devices, web services, or third-party tools:

• Local tests with tox run successfully. Your PR cannot be merged unless tests pass