--- updatedAt: 2026-07-24T00:27:33.000Z agentTools: projectIndex: https://docs.lumeo.com/llms.txt --- # Presence Monitor Extracts occupancy information for objects present in a specified region of interest. # Overview The Presence Monitor node tracks how long each detected, tracked object has been present in the specified region in the video, can highlight objects and generate max time/occupancy level alarms, and adds the presence metadata to the frame metadata. It is designed for monitoring use cases. This node generates presence metrics: current occupancy, objects above max time threshold, occupancy above/below max thresholds. > This node requires a [AI Model Node](https://docs.lumeo.com/docs/ai-model-node) and a [Track Objects Node](https://docs.lumeo.com/docs/track-objects-node) before it in order to function properly. > This node is a simplified version of the [Occupancy Monitor](https://docs.lumeo.com/docs/occupancy-monitor-node). Use the Occupancy monitor if you need to collect statistics such as wait times, people flow, etc. for dashboards, reporting and business intelligence. # Inputs & Outputs * Inputs : 1, Media Format : Raw Video * Outputs : 1, Media Format: Raw Video * Output Metadata : Presence Information # Properties | Property | Description | Type | Default | Required | | ------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------- | ---------- | -------- | | `roi_labels` | Regions of interest labels | `string` | — | No | | `rois` | Regions of interest. Conditional on `roi_labels`. Format: comma-separated normalized `x,y` coordinate pairs; separate multiple polygons with semicolons (for example, `0.1,0.1,0.9,0.1,0.9,0.9`). | `string` | `null` | No | | `objects_to_track` | ex. `car`,`person`,`car.red`. Object types and classes to include. Leave blank to include all. | [model-labels](https://docs.lumeo.com/docs/model-labels) | `null` | No | | `min_presence_time` | Min. time an object should be present in the ROI in order to be considered present. Unit: seconds. | `float` | `1.0` | Yes | | `max_presence_time` | Create an alarm and shows an orange bounding box around object if present more than specified seconds in the ROI. Unit: seconds. | `float` | `null` | No | | `max_occupancy_threshold` | Set a trigger when number of objects in the ROI exceeds or drops below this threshold. | `number` | `null` | No | | `crossing_buffer` | Interval during which an object will not be repeatedly counted if it leaves and reenters the ROI. Unit: seconds. | `float` | `1.0` | Yes | | `object_types_to_flag` | Flag specific objects so you can trigger downstream events using those. Options: Currently in ROI (`current`); Newly entered into ROI (`entry`); Above max presence time in ROI (`above_max_time`); Upon exit from ROI (`exit`). Format: array of selected option values. | `string[]` | `null` | No | | `trigger_events` | Triggers these events. Leave blank to not trigger any events. Options: Object enters ROI (`enter`); Object exits ROI (`exit`); Object above max time in ROI (`max_wait`); ROI below max occupancy threshold (`below_max_occupancy`); ROI above max occupancy threshold (`above_max_occupancy`); ROI contains all specified objects (`all_objects_present`). Format: array of selected option values. | `string[]` | `null` | No | | `event_template` | Template for enter/exit/max\_wait events. Leave blank to use defaults. Available variables: `{object_type}`, `{object_attributes}`, `{state}`, `{roi}`. | `string` | `null` | No | | `add_object_attributes` | Add specified labels as attributes to objects that interact with the ROI. ROI States include enter/exit/max *wait. Options: None (`none`); State (enter/exit/max\_wait) (`state`); ROI Name (`roi`); * (`roi_state`). | `enum` | `none` | No | | `display_roi` | Display ROI? | `bool` | `true` | No | | `display_roi_meta` | Display ROI Statistics? Options: None (`none`): Do not display; Basic (`basic`): Display Occupancy counts only. | `enum` | `detailed` | No | | `display_objects` | Display objects? Options: None (`none`): Do not display; Basic (`basic`): Tracking point only; Detailed (`detailed`): Tracking point and time. | `enum` | `detailed` | No | | `tracking_mode` | Tracking mode. Options: Centroid (`centroid`); Top center (`top-center`); Bottom center (`bottom-center`); Left center (`left-center`); Right center (`right-center`). | `enum` | `centroid` | No | # Events Triggering specific events using `trigger_events` and `event_template` fields allows you to add Events to metadata. These Events can then be processed by downstream nodes to publish metrics to a Dashboard, or send notifications or trigger alarms / bookmarks. # Output Metadata The fields below are declared by this node's metadata schema; the JSON values are representative examples. | Path | Type | Description | | ----------------------------------------------------------------------- | --------- | ----------------------------------------------------------------------------------- | | `nodes..rois..current_occupancy` | `integer` | Number of objects currently occupying the ROI. | | `nodes..rois..objects_entered_delta` | `integer` | When one or more new objects enter the ROI | | `nodes..rois..objects_exited_delta` | `integer` | When one or more objects leave the ROI | | `nodes..rois..objects_above_max_waiting_time_count` | `integer` | Number of objects whose waiting time exceeds the configured maximum. | | `nodes..rois..objects_above_max_waiting_time_delta` | `integer` | When one or more objects exceeds the maximum waiting time | | `nodes..rois..objects_above_max_occupancy_count` | `integer` | Number of objects above the configured occupancy limit. | | `nodes..rois..objects_below_max_occupancy_count` | `integer` | Number of objects within the configured occupancy limit. | | `nodes..rois..occupancy_above_max_threshold_delta` | `integer` | When occupancy equals or exceeds Max Threshold | | `nodes..rois..occupancy_below_max_threshold_delta` | `integer` | When occupancy falls below Max Threshold | | `nodes..rois..objects_flagged_count` | `integer` | Number of objects currently matching this node’s alert criteria. | | `nodes..rois..objects_flagged_delta` | `integer` | When one or more objects is newly flagged | | `nodes..rois..all_objects_present` | `boolean` | Boolean indicating whether all configured object classes are currently present. | | `nodes..rois..all_objects_present_delta` | `boolean` | When all specified object types are present in the ROI | | `nodes..rois..all_objects_not_present_delta` | `boolean` | When all specified object types are not present in the ROI | | `nodes..rois..coords` | `array` | Array of pixel coordinates defining the configured ROI or line. | | `nodes..rois..objects_of_interest_keys` | `array` | Array of metadata keys that contain object IDs relevant to downstream integrations. | | `nodes..rois..objects_flagged` | `array` | Array of tracking IDs of objects currently matching this node’s alert criteria. | | `nodes..rois..description` | `string` | Human-readable summary of the node’s current result. | | `nodes..events_delta` | `integer` | When one or more Presence events are triggered | | `nodes..events` | `array` | Array of event names generated by this node for the current frame. | | `nodes..type` | `string` | Identifies the node type that produced this metadata. | ## JSON example ```json { "nodes": { "annotate_presence1": { "events": [], "events_delta": 0, "rois": { "roi1": { "all_objects_not_present_delta": false, "all_objects_present": true, "all_objects_present_delta": false, "coords": [ [ 468, 172 ], [ 597, 307 ] ], "current_occupancy": 1, "description": "value", "objects_above_max_occupancy_count": 0, "objects_above_max_waiting_time_count": 1, "objects_above_max_waiting_time_delta": 0, "objects_below_max_occupancy_count": 0, "objects_entered_delta": 0, "objects_exited_delta": 1, "objects_flagged": [ "12837198712897", "1231293712897612" ], "objects_flagged_count": 0, "objects_flagged_delta": 0, "objects_of_interest_keys": [], "occupancy_above_max_threshold_delta": 0, "occupancy_below_max_threshold_delta": 0 } }, "type": "annotate_presence" } } } ``` ## Object labels and attributes * **Object labels/classes added:** No new class is created. The node can reinsert a tracked upstream object, preserving its original label and class. * **Object attribute labels/classes added:** Depending on `add_object_attributes`, the presence state (`enter`, `exit`, or `max_wait`) uses class `35101`, the ROI label uses class `35102`, and `_` uses class `35103`.