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Object Presence with Absence of Another

Object Presence with Absence of Another is a query that detects the presence of one object type while another object type is absent. The query uses the following parameters:

Prerequisites

Setup

  1. Select a video from your workspace Click +Set up New Query.

  2. Select Object Presence with Absence of Another from the list of query types.

1. Query Name

Give your query a name to better identify it. A description can also be added (optional).

2. Object Presence Filter

Videos

The thumbnail image of the previously chosen video is displayed here.

Time interval

Time interval

Select a time frame for the analytics to run, depending on the type of video selected above:

  • Earliest: Run the query from the time shown (set during video registration as the beginning timestamp of the video).
  • Latest: Run the query until the time shown (set during video registration as the end timestamp of the video).
  • Given Date: You can select a custom start and end date and time to run the query on. Type the desired date and time or select them by clicking the calendar icon.
  • Live: Analysis is run live, continously.
  • Interval: You can select a custom start and end date and time to run the query on. Type the desired date and time or select them by clicking the calendar icon.
  • Set interval to: Choose from the presets below to run the query on a given time inmterval.

Object types

Select one or multiple object types you want to search for - Person is selected by default. Select a category, then click the dropdown menu to see the list of available object types for the selected object category.

Object types

  • Minimum confidence (0.5 by default): The minimum confidence level required for an object to be detected. The higher the confidence level, the more certain the system is that the object is of the selected type. The confidence level ranges from 0 to 1, with 1 being the highest confidence level.

ROI (Region of Interest)

Draw a polygon on the video frame to define the area where the objects will be detected. The polygon can be drawn by clicking on the video frame to create points, then clicking the first point to close the polygon.

  • Sampling interval (in seconds, 5 by default): The rate at which the video frames are sampled for analysis. The higher the sampling rate, the more frames are analyzed, which may increase the accuracy of the results but also the processing time.

  • Maximum number of parallel tracks at the same time (50 by default): The maximum number of tracks that can be processed simultaneously. Increasing this number may improve the accuracy of the results but also the processing time.

3. Object Absence Filter

Videos

The thumbnail image of the previously chosen video is displayed here.

Object types

Select one or multiple object types you want to search for - Person is selected by default. Select a category, then click the dropdown menu to see the list of available object types for the selected object category. - Minimum confidence (0.5 by default): The minimum confidence level required for an object to be detected. The higher the confidence level, the more certain the system is that the object is of the selected type. The confidence level ranges from 0 to 1, with 1 being the highest confidence level.

ROI (Region of Interest)

Draw a polygon on the video frame to define the area where the objects will be detected. The polygon can be drawn by clicking on the video frame to create points, then clicking the first point to close the polygon.

  • Sampling interval (in seconds, 5 by default): The rate at which the video frames are sampled for analysis. The higher the sampling rate, the more frames are analyzed, which may increase the accuracy of the results but also the processing time.
  • Maximum number of parallel tracks at the same time (50 by default): The maximum number of tracks that can be processed simultaneously. Increasing this number may improve the accuracy of the results but also the processing time.
  • Window length (in milliseconds, 10000 by default): The time window in which the object presence and absence are detected. The higher the window length, the more time the system has to detect the objects, which may increase the accuracy of the results but also the processing time.

4. Alarm Integration (optional)

The query can optionally be integrated with third-party systems, such as Milestone XProtect or a webhook to trigger alarms.

Milestone XProtect Analytics Event Integration

The query can be configured to send detections to Milestone XProtect, appearing as Analytics Events.

  • Cooldown (in seconds, 10 by default): The minimum time between two alerts sent to the chosen integration.

  • Milestone XProtect host address: The IP address of the Milestone XProtect server.

  • Analytics event name: The name of the Milestone XProtect Analytics Event that triggers the query.
  • Event display name: The display name of the event that will be shown in the event list.
  • Description: The description of the event that will be shown in the event list.
  • Timestamp offset (in seconds): The time offset between the Milestone XProtect Analytics Event and the query trigger.

Webhook

The query can be configured to send detections to a Webhook URL.

  • URL: The URL of the Webhook.
  • Custom header key: The key of the custom header.
  • Custom header value: The value of the custom header.

Results

All done - Clicking Save & Run will immediately start the analysis and opens the Result screen of this query. Alternatively, clicking Save & Exit saves the query without running it.