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Glossary

The glossary explains terms commonly used in Frigate's documentation.

Alert​

The higher-priority of the two review item severities, the other being a detection. By default a review item is an alert when it involves a person or car; the qualifying labels and zones can be configured. See the review docs for more info

Attribute​

A property detected on an object that exists alongside its label. Unlike a sub label, an object can carry several attributes at once. Some attributes come directly from the object detection model — for example face, license_plate, or delivery carrier logos such as amazon, ups, and fedex — while others come from a custom object classification model configured with the attribute type. Attributes are visible in the Tracked Object Details pane in Explore, in frigate/events MQTT messages, and through the HTTP API.

Bounding Box​

A box returned by the object detection model that outlines a detected object in the frame. In the Debug view, bounding boxes are colored by object label.

Bounding Box Colors​

  • At startup different colors will be assigned to each object label
  • A dark blue thin line indicates that object is not detected at this current point in time
  • A gray thin line indicates that object is detected as being stationary
  • A thick line indicates that object is the subject of autotracking (when enabled)

Class​

The categories a classification model is trained to distinguish between. Each class is a distinct visual category the model predicts, plus a none class for inputs that don't fit any category. For example, a custom object classification model for person objects might use the classes delivery_person, resident, and none. The predicted class is applied to the object as either a sub label or an attribute, depending on the model's configuration. See the object classification docs for more info

Detection​

The lower-priority of the two review item severities, the other being an alert. By default, any review item that does not qualify as an alert is a detection; the qualifying labels and zones can be configured. Despite the name, a detection is a category of review item — not the same as the object detection performed by the model. See the review docs for more info

False Positive​

An incorrect result from the object detection model, where it assigns the wrong label to something in the frame — for example a dog identified as a person, or a chair identified as a dog. A person correctly identified in an area you want to ignore is not a false positive.

Label​

The type assigned to a detected object by the object detection model, drawn from the model's labelmap — for example person, car, or dog. Frigate tracks person by default; additional labels are tracked by adding them to the objects configuration. See the available objects docs for the full list

Mask​

There are two types of masks in Frigate. See the mask docs for more info

Motion Mask​

A motion mask stops motion in the masked area from triggering object detection. It does not stop an object from being detected when object detection runs because of motion in a nearby area. Use motion masks for parts of the frame that change constantly but never contain objects you care about — camera timestamps, the sky, the tops of trees, and so on.

Object Mask​

An object filter mask drops any bounding box whose bottom center falls inside the masked area (overlap elsewhere doesn't matter). The object is forced to be treated as a false positive and ignored.

Min Score​

The lowest score a detected object can have to be kept during tracking. Anything scoring below the minimum is assumed to be a false positive and discarded.

Model​

A machine learning model that Frigate uses to detect or classify objects. The object detection model locates objects in each frame and returns their labels and bounding boxes. Additional enrichment models run on tracked objects to add detail: face recognition, license plate recognition, bird classification, custom object and state classification, and the embedding models used for semantic search. See the object detectors docs for more info

Motion​

A change in pixels between the current camera frame and previous frames. When many nearby pixels change together, they are grouped and shown as a red motion box in the debug live view. See the motion detection docs for more info

Object​

Something Frigate can detect and follow in a camera frame, identified by its label (for example a person or a car). The object types Frigate watches for are set in the objects configuration. Once an object is detected and followed across frames it becomes a tracked object, which may also carry a sub label and attributes. See the available objects docs for more info

Region​

A portion of the camera frame sent to the object detection model. Regions are selected because of motion, active objects, or occasionally to recheck stationary objects, and are shown as green boxes in the debug live view.

Review Item​

A period of time during which one or more tracked objects were active, grouped together for review. Each review item is categorized as either an alert or a detection. See the review docs for more info

Snapshot Score​

The object's score at the specific moment the snapshot was captured.

Sub Label​

A more specific identity assigned to a tracked object in addition to its label. A person may get the name of a recognized face, a car may get the name of a known license plate, and a bird may get its species. An object can have only one sub label at a time. Sub labels are produced by face recognition, license plate recognition, bird classification, custom object classification configured with the sub label type, and semantic search triggers.

Threshold​

The median score an object must reach to be considered a true positive.

Top Score​

The highest median score an object reached over its lifetime.

Tracked Object ("event" in previous versions)​

An object followed from the moment it enters the frame until it leaves, including any time it stays still. A tracked object is saved once it is considered a true positive and meets the requirements for a snapshot or recording.

Zone​

A user-defined area of interest within the camera frame. Zones can be used for notifications and to limit where Frigate creates a review item. See the zone docs for more info