Start FFmpeg sensor

Use this action to start an FFmpeg sensor, so it begins analyzing its camera or audio stream again. For example, you only want motion detection on the driveway camera while you’re away.

This action works with the binary sensors of the FFmpeg motion and FFmpeg noise integrations, which use FFmpeg to analyze a camera or audio stream.

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 start an FFmpeg sensor 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. From the search box, search for and select Start.
6. Optional: In Entity, select the FFmpeg sensor. Leave it empty to start all FFmpeg sensors.
7. Select Save.

This action does not support targets. You choose the sensor with the Entity option instead.

Options in the UI

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 ffmpeg.start. A basic example looks like this:

action: ffmpeg.start
data:
  entity_id: binary_sensor.driveway_motion

This starts the binary_sensor.driveway_motion sensor.

Options in YAML

Good to know

• A sensor set up with initial_state: false doesn’t start by itself when Home Assistant starts. Use this action to start it.
• If the sensor is already running, this action has no effect.

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: start motion analysis when you leave

When you leave home, you want to know about motion on the driveway camera. This automation starts the FFmpeg motion sensor when you leave.

• Trigger: Zone
  • Entity with location: You (person.you)
  • Zone: Home
  • Event: Leave
• Action: Start
  • Entity: Driveway motion (binary_sensor.driveway_motion)

alias: "Start driveway motion analysis when I leave"
triggers:
  - trigger: zone
    entity_id: person.you
    zone: zone.home
    event: leave
actions:
  - action: ffmpeg.start
    data:
      entity_id: binary_sensor.driveway_motion

Automation: start listening in the nursery at bedtime

Start the FFmpeg noise sensor of the nursery camera at 19:30, so you know when the baby wakes up.

• Trigger: Time
  • At time: 19:30
• Action: Start
  • Entity: Nursery noise (binary_sensor.nursery_noise)

alias: "Start the nursery noise sensor at bedtime"
triggers:
  - trigger: time
    at: "19:30:00"
actions:
  - action: ffmpeg.start
    data:
      entity_id: binary_sensor.nursery_noise

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.

Related actions

Explore related actions:

• Stop FFmpeg sensor: Stops analyzing the stream of an FFmpeg-based sensor.

• Restart FFmpeg sensor: Stops and starts an FFmpeg-based sensor again.