Tensorflow: Multiple cameras with custom cropping and categories

Home Assistant: 0.92.0 on Docker version 18.06.0-ce, build 0ffa825
Dockerfile is customized to add OpenCV for Tensorflow - Gist

What is the correct way to setup multiple tensorflow image_processing instances with unique settings?

I am currently creating 4 tensorflow entries in config so that I can customize the model and area. Calling image_processing.scan only works on one entry. All of the entries show up in the entity options in the services section.

Logs

[homeassistant.components.image_processing] Setting up image_processing.tensorflow
[homeassistant.components.image_processing] Setting up image_processing.tensorflow
[homeassistant.components.image_processing] Setting up image_processing.tensorflow
[homeassistant.components.image_processing] Setting up image_processing.tensorflow
[homeassistant.components.image_processing] Setup of platform tensorflow is taking over 10 seconds.
[homeassistant.components.image_processing] Setup of platform tensorflow is taking over 10 seconds.

Configuration

image_processing:
  - platform: tensorflow
    scan_interval: 604800
    source:
      - entity_id:  camera.driveway_lowres
    file_out:
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_latest.jpg"
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_{{ now().strftime('%Y%m%d_%H%M%S') }}.jpg"
    model:
      graph: /config/tensorflow/frozen_inference_graph.pb
      categories:
        - dog
        - person
        - category: car
          area:
            top: 0.1
            left: 0.21
        - category: truck
          area:
            top: 0.1
            left: 0.21
  - platform: tensorflow
    scan_interval: 604800
    source:
      - entity_id: camera.front_yard_lowres
    file_out:
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_latest.jpg"
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_{{ now().strftime('%Y%m%d_%H%M%S') }}.jpg"
    model:
      graph: /config/tensorflow/frozen_inference_graph.pb
      categories:
        - dog
        - person
        - car
        - truck
  - platform: tensorflow
    scan_interval: 604800
    source:
      - entity_id: camera.kitchen
      - entity_id: camera.northgate
      - entity_id: camera.backyard
    file_out:
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_latest.jpg"
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_{{ now().strftime('%Y%m%d_%H%M%S') }}.jpg"
    model:
      graph: /config/tensorflow/frozen_inference_graph.pb
      categories:
        - dog
        - person
  - platform: tensorflow
    scan_interval: 604800
    source:
      - entity_id: camera.southgate
    file_out:
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_latest.jpg"
      - "/config/www/tensorflow/{{ camera_entity.split('.')[1] }}_{{ now().strftime('%Y%m%d_%H%M%S') }}.jpg"
    model:
      graph: /config/tensorflow/frozen_inference_graph.pb