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Motion sources: pixel, Frigate, and Home Assistant

Crumb's own detectors work on raw pixel motion; they don't know the difference between a person, a car, and a blowing branch. That pixel analysis is one of three things that can trigger recording on a camera, and you can turn each one on independently:

  • Pixel analysis (Crumb), the default: Crumb's own motion detection on the camera's sub-stream.
  • Frigate detections: recording is triggered by Frigate's neural object events (person, car, package, and so on).
  • Home Assistant sensors: recording is triggered by linked Home Assistant motion or door/window sensors (PIR, occupancy, a contact sensor).

These are additive. A camera records on the union of whichever sources you enable, so you can run pixel analysis and Frigate together, Frigate on its own, pixel plus a door sensor, or any other combination. In the camera editor's Motion tab, each source is a separate checkbox.

Frigate and Home Assistant are both entirely optional and entirely bring-your-own: Crumb does not bundle or run either one, and pixel motion detection keeps working the same whether or not an integration is configured. See Integrations for the setup steps and what data flows where.

Detections on the timeline (independent of the trigger)​

Turning a source on as a trigger is separate from showing its events on the timeline. Whenever Frigate or Home Assistant is connected, their events (object labels from Frigate, door/window/motion from Home Assistant) show up as their own icons on the same timeline as pixel motion, distinguishable at a glance, whether or not you've made them a recording trigger for that camera. So you can leave a camera on pixel motion for recording and still get a smart, labelled timeline from an integrated detector.

Using Frigate or Home Assistant as the trigger (per camera)​

You can let object detections or a sensor drive recording for a specific camera instead of, or alongside, pixel motion. Crumb translates a source's "something is happening now" into the same start and stop signal the pixel pipeline emits, so recording, pre-roll, and post-roll behave identically no matter which source fired; only the trigger differs.

The reason to lean on Frigate or a sensor is precision. On a camera pointed at a busy street or moving foliage, pixel motion fires constantly on things you don't care about, whereas an object detector only fires on an actual person or vehicle, and a PIR or door sensor only fires on real physical events. Turning off pixel analysis for just that camera and leaving Frigate (or the sensor) on removes the nuisance recordings.

The trade-off, read this before turning pixel motion off​

Object- or sensor-triggered recording is precise, but on its own it is not fail-safe. If the only enabled source doesn't report anything, Crumb records nothing for that camera in that window:

  • Pixel motion is fail-safe: any motion records, so it over-records but rarely misses.
  • An object or sensor trigger records only what that source reports, so it can miss real events the source doesn't catch: low light, an object type the detector doesn't track, a detection below its confidence threshold, heavy occlusion, a sensor out of range.

One important exception: a source going unreachable does not silently drop footage. If Frigate's broker disconnects, or Home Assistant can't be polled, or the pixel detector's own task dies, that source is marked unhealthy and the camera fails open, recording everything until the source recovers. Crumb also raises a health alert. So the miss cases above are the source-is-up-but-blind ones, not source-is-down.

For a security camera, missing a real event is usually worse than an extra recording. So treat this as a per-camera decision. Lean on Frigate or a sensor on nuisance-prone cameras where precision matters, and keep pixel analysis (or continuous recording) on cameras where you cannot afford to miss anything. If you want both guarantees at once, run the camera on continuous recording and use the detections purely for timeline highlights: you never miss footage, and you still get a smart, searchable timeline.