Detect Region Tracks dialog box

The Detect Region Tracks dialog box is used to detect region tracks in the current scene.

To display the Detect Region Tracks dialog box: On the Scene menu, click Detect Region Tracks.

Settings

Description

Name region track group

The name for the 3D region track group to be created.

Track regions of class

Specify the region class on which region tracks are to be detected.

Tracking settings

The parameters that specify how predicted positions are determined and used. See region tracking algorithm for detailed descriptions of their use.

Variable	Description
Alpha	A filter factor for position estimates. 1 suggests no confidence in position predictions and 0 suggests total confidence. Lower Alpha values are less sensitive to measurement noise, higher Alpha values are more responsive to target movements.
Beta	A filter factor for velocity estimates. 1 suggests no confidence in velocity predictions and 0 suggests total confidence. Lower Beta values are less sensitive to measurement noise, higher Beta values are more responsive to target movements. Velocity is generally more sensitive to noise than position and Beta is generally lower than Alpha.
Exclusion distance	The permissible distance (m) between a prediction and an observation.

Weights

The parameters that specify how regions are allocated to tracks when more than one track or region is considered at a time. See region tracking algorithm for detailed descriptions of their use.

Variable	Description
Distance in space	Weight for the distance (m) in space between an observed point and the predicted point.
Distance in time	Weight for the time (s) between an observed point and the last point in a track.
Mean Sv	Weight for the difference between the Mean Sv (dB re 1m-1) of a region and the mean Sv mean of the regions in a track.
Volume	Weight for the difference between the volume (m3) of a region and the mean volume of the regions in a track.

Notes:

Weights are relative to one another. You can use any values you like. If one is twice another this will grant that parameter twice the influence of the other in determining region to track allocations.
These are only used where:
there are two or more tracks to which a region may be allocated.
there are two or more regions with exactly the same mean valid time.
This is unlikely to happen if detected schools are tracked.

Track Acceptance

The parameters that specify some constraints with which the resulting 3D region tracks must comply.

Variable	Description
Minimum number of regions in a track	The minimum number of regions a track must contain.
Maximum distance gap between regions	The maximum distance (m) between two points in a track.
Maximum time gap between regions	The maximum time (s) between two points in a track.

Detect Region Tracks dialog box

See also