Slideshow package

slideshow:
  input_select:
    pictures:
      name: "Holder til billeder"
      options:
        - cow_1.jpg
        - cow_2.jpg
        - cow_3.jpg

  automation:
    - alias: "Next picture"
      trigger:
        - platform: time_pattern
          seconds: "/15"
      action:
        - service: input_select.select_next
          data:
            entity_id: input_select.pictures