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Jitter caused by merged blob detections

To detect this issue, look in the four 2D camera views for the jittery point, and check whether any of the blob detections contributing to the point are merged with other blobs as one marker occludes another in one of the camera views.

Fixing merged blob detections

Make use of the Blob Size Difference Threshold tracking parameter to force the tracking process not to use the merged blob detections. To do this:

1.    Set the Active Range for the take to the frame-range in which the merged detections are present.

2.    Select the marker point where the merged detections are present, and detach the incorrect detections across the Active Range by clicking Edit > Detach Detections [Active Range].

Tip:          If needed you can detach detections in specific camera views only by selecting the appropriate channel(s) in the Selection pane.

3.    Set the Blob Size Difference Threshold tracking parameter to a very low value (e.g. around 0.1).

4.    Navigate to the frame before you have detached the detections, and re-track the selected marker point forwards across the required frame range.

In frames where there are merged detections, the tracker should now patch-track instead.

If the above approach fails, use the Target Tracker (see Target tracking) to perform completely manual re-tracking of the point over the problematic range.