How to Fix Frigate Zone Filters Missing Expected Events
- Object's anchor point not entering the zone
- Zone polygon coordinates wrong
- Zone object filter too strict
Problem Description
You defined a zone in Frigate but expected detection events are not triggering — people walk through the zone area but no zone events appear in the event list or MQTT feed. The zone coordinates may not cover the intended area, the object type filter may exclude the detected object class, the zone boundary may be too tight, or the zone inertia setting requires more consecutive frames than the object spends in the zone.
Why This Happens in Real Homes
Frigate zones missing expected events usually comes down to how zone entry is judged: an object is considered "in" a zone when its anchor point (by default the bottom-center of the bounding box, roughly where a person's feet are) enters the polygon — not just when any part of the box overlaps. So a person whose feet are outside the zone won't count, even if their body overlaps it.
Check that the zone polygon covers where the object's anchor point actually travels, and correct the coordinates (they're in detect-resolution pixels, so a resolution mismatch shifts them). Loosen any object filter on the zone that's limiting which objects count, and confirm detection is happening in that area at all. Adjusting the zone shape to capture the anchor point's path is what makes it register the events.
Symptoms
- Zone missing expected events
- Object in the zone not counted
- Zone filter too strict
- Events not attributed to the zone
- Zone doesn't trigger
- Object enters but no zone event
- Zone coordinates seem off
- Missing zone detections
Recognize these? Here's what usually causes it.
Common Causes
- Object's anchor point not entering the zone
- Zone polygon coordinates wrong
- Zone object filter too strict
- Zone too small/mispositioned
- Detection not occurring in the area
- Zone requires more of the object inside
- Coordinate/resolution mismatch
- Misunderstanding zone entry logic
Most fixes happen in the first 3 steps.
Over-tight zones can silently suppress high-value events.
Tools & Requirements
Step-by-Step Solution
Verify the zone coordinates are correct
Zone coordinates define a polygon on the detect frame. If the coordinates do not cover the area you expect: objects in that area are not counted as 'in zone.' Use the Frigate web UI zone editor to draw zones visually — this is much easier than calculating pixel coordinates manually. Click the camera view, select the zone/mask editor, and draw the polygon over the area you want to monitor. The editor shows the coordinates, which you can copy into frigate.yml.
Check that objects actually enter the zone
An object must be detected inside the zone boundaries to trigger a zone event. If a person walks along the edge of a zone but their detection center point never crosses into the zone: no zone event is generated. Frigate tracks the center of the bounding box, not the full box. Make zones slightly larger than the actual area of interest to account for bounding box offset — especially for objects at the edge of the camera view where perspective distortion affects bounding box position.
Check zone filters for object type
Zones can filter by object type. If the zone has objects: [car] but you expect person detections: person events in that zone are filtered out. In frigate.yml: cameras: your_camera: zones: your_zone: objects: [person, car] to detect both. If the objects list is omitted: all detected object types trigger the zone. Also check: filters: your_zone: min_score: 0.7 — if the score threshold is too high, low-confidence detections (distant objects, partial occlusions) are filtered out.
Verify zone events in the Frigate UI
Go to the Frigate web UI events page and filter by the specific zone name. If events appear in the zone filter: zone detection is working and the issue is in your Home Assistant automation or MQTT subscriber. If no events appear for the zone: check the detection overlay — enable debug view for the camera and verify that detected objects and zone boundaries overlap when you expect them to.
Check for zone inertia settings
Frigate supports zone inertia — the number of consecutive frames an object must be detected inside a zone before it counts as a zone entry. Default is 3 frames. If inertia is set high (10+): fast-moving objects that cross the zone in fewer frames are not counted. Lower inertia for small zones or areas where objects move quickly: zones: your_zone: inertia: 3. For large zones where objects linger: higher inertia reduces false zone entries from detection jitter.
Quick Solutions
Still having issues? This is usually the deeper cause below.
If this comes back after following these steps, check whether a recent app or firmware update reset a default setting — the fix works, but the setting gets reverted silently.
Zone tuning should be based on recorded real-world paths, not static assumptions.
This issue almost always looks more complex than it is — the majority of cases trace back to a single setting, a stale credential, or a default that shipped wrong.
- Object's anchor point not entering the zone
- Zone polygon coordinates wrong
- Zone object filter too strict
- Zone too small/mispositioned
- Detection not occurring in the area
Before you go — try one of these (they fix most cases).
Official Manufacturer Manual
Frigate provides official product documentation through their online manual rather than downloadable PDF. Access setup guides, troubleshooting steps, and product specifications for your Frigate Zone Filter Tuning.
Source: docs.frigate.video
Need More Help? Frigate Support
Note: The contact information below connects you directly to Frigate's official customer support team, not Trunetto. They can help with warranty claims, device replacements, and advanced technical issues.