Scan image

Use this action to make an image processing entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] process the current image from its camera right away, instead of waiting for its next scheduled run.

This is the usual way to keep image processing efficient. Set a long scan interval so the entity almost never processes on its own, and run this action at the moments that matter, such as when a motion sensor goes off.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To process an image from an automation or a script:

1. Go to Settings > Automations & scenes.
2. Open an existing automation or script, or select Create automation > Create new automation.
3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger. They run when something else calls them.
4. In the Then do section, select Add action.
5. Select what you want to control. Under By target (see Targets), select the image processing entity you want to run.
6. From the actions shown for that target, select Scan.
7. Select Save.

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required.

In YAML, refer to this action as image_processing.scan. A basic example looks like this:

action: image_processing.scan
target:
  entity_id: image_processing.door

This processes the current image from the camera behind image_processing.door.

Targets of the action

This action requires a target. The target is the object of the action. You can point the action at a single entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more], a device, an area, a floor, or a label, and Home Assistant will run the action on every matching image_processing entity behind that target.

• Entity: one specific image_processing entity, such as image_processing.living_room.
• Device: every image_processing entity that belongs to a device.
• Area: every image_processing entity in a room or area.
• Floor: every image_processing entity on a floor.
• Label: every image_processing entity that shares a label.

You can also select different target types in one action. For example, you can add a specific entity and an area as targets in the same action to run the action on both of them at once.

Good to know

• Processing sometimes takes a long time. The result shows up in the state and attributes of the entity after it’s done, and any events the platform sends, such as image_processing.detect_face, follow afterward.
• Image processing entities process on a schedule set by their scan_interval, which is 10 seconds by default. Set a long interval and use this action instead if you only need results at specific moments.
• Only camera entities can be used as the image source. See Image processing for what these entities report.

Try it yourself

Ready to test this? Open Settings > Tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup.

Automation: scan for faces when motion is detected

Process the camera image at the door only when the motion sensor picks something up.

• Trigger: Motion detected
  • Target: Door motion sensor
• Action: Scan
  • Target: Door

- alias: "Scan for faces when motion is detected"
  triggers:
    - trigger: motion.detected
      target:
        entity_id: binary_sensor.door_motion_sensor
  actions:
    - action: image_processing.scan
      target:
        entity_id: image_processing.door

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.