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BriefCam Administrator Guide

Proximity Settings

Last Updated: 2 minute read

Caution

This functionality is not applicable for the Hub. It is only relevant for sites and in standalone deployments.

For all modules, to set the maximum real-word coordinates that an object will have, use the MaxLocationXY parameter in the OX.ini file (located at: C:\Program Files\BriefCam\BriefCam Server). The default value is 35.3 meters, which will enforce a maximum distance of 99.84. The calculation for this is:

Proximity equation.png

This threshold handles situations when in some cases of objects near the horizon (even if they are just meters away) they get very large X,Y distances, such as 3,000 meters. The threshold is defined on the XY location, that is the distance in meters from the ground plain’s center (=image center). This means that the valid X,Y values are between +/-100 meter, and the distance between two objects might be greater than 100 meters.

The environment settings that can be used to control the Proximity feature in the RESEARCH module are:

  • BIRuleEngine.RESEARCHProximityEnabled – Determines whether the Proximity calculation in the RESEARCH module is enabled or disabled (default). Enabling the Proximity calculations in the RESEARCH module will consume extra CPU resources.

  • BIRuleEngine.RESEARCHProximityDurationTimeThresholdInSeconds – The minimum duration time that counts as actual exposure between two personas (by default 15 seconds).

  • BIRuleEngine.RESEARCHProximityDurationPercentageThreshold – The minimum proximity duration percentage to consider two personas as associated and should be ignored for the proximity calculations (by default 0.8, meaning 80%).

  • BIRuleEngine.RESEARCHProximity.MinProximityThresholdInCm – The minimum proximity that counts as exposure (by default 200 cm).

X-Y Location Sampling Rate

The XYLocations.SampleRate environment setting lets the administrator change how often (in seconds) a person's XY location is sampled. The valid input for this setting is 1-900. For Proximity detection, set the sampling interval so that is small enough to ensure that there is continuous proximity – but not too small as to waste CPU resources unnecessarily. For example, if you would like to detect proximities of 5 minutes, changing the sampling rate to 2 minutes might be too slow as perhaps during these 2 minutes objects moved further away from each other. A 30-60 second sampling rate might be adequate, but a sampling rate of every second might be excessive. In general, for proximities of 5-15 minutes, in order to utilize minimal system resources, it is recommended to set this setting to 10-60 seconds per sample.