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Line Crossing Detection with Face Recognition

This Query Type detects when entities matching a given image set cross a line within a specified time interval. It is primarily intended to be used for identifying specific individuals entering or exiting an area.

Prerequisites

Setup

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

  2. Select Line Crossing Detection 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 Detection 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 interval.

Line cross attributes

Linecross

Draw a line on the canvas to define the area where objects crossing the line will be detected. The line can be drawn in any direction, and it will be used to determine whether an object has crossed it.

Left-click on the camera thumbnail to begin drawing the line; left-click again to finish drawing. Select from the options below the canvas to select the facing direction.

  • Ignore duplicate crossings (in milliseconds, 1000 by default): If multiple crossings of the same tracked object occur within the selected amount of time, only one event will be fired for that object. Use this option to avoid counting the same object multiple times, e.g. when a person is walking back and forth across the line.

  • Use bottom reference point: Choose either the center or the bottom of the bounding box as a reference point to determine whether the object is within the ROI.

  • 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.

Face profiles

Select an image set containing images of faces you want to detect. The image set must contain images of faces that you want to match against the detected objects crossing the line.

Emit mode:

  • Match: Only gives results for objects that match the faces in the image set.
  • Non match: Only gives results for objects that do not match the faces in the image set.

3. Alarm Integration (optional)

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.