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Multiple Crossline Counting

Multiple Crossline Counting is a query that counts the number of objects crossing exactly two lines.

1. Query Name

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

Prerequisites

Setup

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

  2. Select Multiple Crossline Counting from the list of query types.

2. Object Detection Filter (1st line)

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.

Line cross attributes

The detector filters results to objects that cross both lines in directions set here.

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.

  • More cross one firing (in milliseconds, 1000 by default): The minimum time between two objects crossing the line to trigger an alert.

  • 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.

3. Object Detection Filter (2nd line)

  • 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.

Line cross attributes

The detector filters results to objects that cross both lines in directions set here.

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.

  • More cross one firing (in milliseconds, 1000 by default): The minimum time between two objects crossing the line being counted as a crossing.

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

  • 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.

4. Space join

  • Maximum time difference (in milliseconds, 5000 by default): The maximum time difference between objects crossing the two lines. If the time difference is less than the value set here, it will be counted as a crossing.

  • Join order (free by default): The order in which the objects have to cross the lines.

5. Time-based Segmentation

The query separates cross counts into time windows, configured here. By default, crosses are displayed in 5-second intervals.

  • Length (in milliseconds, 5000 by default): The length of one time window.

4. External Integrations (optional)

The query can optionally be integrated with third-party systems, such as a webhook.

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

The results of the query are displayed in a table format, showing the number of detected objects for each time window. The table can be filtered and sorted based on various parameters.

Read more about the results in the Results section.