2D
2.5D
3D Tracking

 
Y

Choose how you would like to track the ID tags:

"2D Tracking" works only with one active camera (that does not need to be calibrated in XYZ-space).
The result for the tag(s) is a position described with X and Y, there is no Z-coordinate! The X- and Y-values depend on the resolution of the used camera, hence their unit is pixel. To scale the values down, e.g. to follow with a Video Layer, you can use a Range Filter node.
If you calibrate the XYZ-position of the camera, the output values are in meters and independent from the camera resolution.

"2.5D Tracking" works with one or several active cameras. They need to be calibrated in XYZ-space.
The result for the tag(s) is a position described with X and Z, both represented in meter values and depending on the XZ-movement of the tag. The Y-coordinate does exist, but is independent from the real up-down-movement. Set a constant height with the "Y" number field.

"3D Tracking" works with several active cameras. At least three cameras must see a tag at every time. The cameras need to be calibrated in XYZ-space.
The result for the tag(s) is a position described with X, Y and Z, all represented in meter values and depending on the real XYZ-movement of the tag.

Mode

The mode (consisting of two figures) must match the "Mode" and "Interval" used when configuring the tags.

Blink ID

This option allows high tracking distances.

Per default, the option "Blink ID" is on. As soon as you exceed tracking distances of 10m, this option must be ticked.
If you track with lower distances and you have problems detecting a tag ID it might be that the exposure is too high. In that case the off state in the blinking still produces a little bit of light and disturbs the detection.
For distances below 1m, reducing the exposure might not be sufficient. In that case, deactivate the "Blink ID" option.

An deactivated "Blink ID" option detects the on and off states of the blinking by comparing brighter and darker pixels. This method allows maximum tracking distances of 5m and requires slow movement towards the camera lens.

Double Check ID

This influences the behavior of keeping the tag ID in case of an error. This does not apply for the initial recognition of a tag which is always a double check, i.e. an ID is initialized as soon as it is recognized twice. During and after recognition, tags transfer their ID with a blinking pattern. As an exception, it might happen that the pattern is not identified as the same ID as before, it can either be lost or identified as a different ID. This can happen when the tag is not seen by the cameras, e.g. when it disappears behind a set piece or is hidden by another object for a moment.

Per default, the option "Double Check ID" is off. In case the ID is stable for a long time and then changes or disappears for a short time, this error weighs comparatively little. The "Off" option allows to soften or damp errors. As long as a blinking light is seen within the diameter set up with "Max Motion" (in "2D Camera Tracking Settings") it is assumed that it is the ID it was in the last frames.

If "Double Check ID" is ticked, errors are not seen relatively but count absolutely. Even if a tag ID changes or disappears for one moment, this counts. The old ID is removed and deactivated if the error occurred for at least the number of the "Hold" frame count set up in "2D Camera Tracking Settings".
If you activate "Double Check ID" it is very important that the tracking recognition is 100% stable as it is demanded that the ID stays constantly the same.

Max Pts

This option defines how many points are examined to "wear" an ID. The information in the left upper corner of the preview depicts how many "points" a camera sees. This is influenced by the exposure and threshold set up in the section "Camera Settings". In best case, the point count matches the ID tag count. Realistically, it is a little higher due to disturbing light. The higher "Max Pts" is, the more performance is needed. It is recommended to increase this option only if necessary. If you decrease it to save performance make sure that the real point count does not exceed it.