For motion capture and data streaming recording to take place, you must create objects. Objects are a rigid, asymmetrical arrangement of at least three markers whose motion data you want to track. Multiple objects can be defined to track many rigid bodies at the same time. If necessary, you can apply different levels of filtration to each object to obtain the required smoothing.
To create an object:
- If you are streaming live, on the Objects tab in the Resources pane, click Pause .
- Ensure that in the Object Tracking Mode section at the bottom of the tab, Track mode is not selected. This enables you to see unlabeled reconstructions in the 3D Perspective view pane.
- In the view pane, zoom in (right-click + drag forward or backward) on the markers to be defined as an object.
- Select the (three or more) markers you want to include by doing one of the following:
- To select markers individually, press and hold the CTRL key while you left-click on each marker.
- To select a group of markers, press and hold the ALT key while you drag around the markers to form a box around them.
With the markers selected, enter a name in the Create Object box and then click Create.
In the Create Object text box, the name is automatically incremented by 1 each time you click Create, so that, to create another object with the default name of ObjectName_n, you can just select the required markers and click Create.
If required, apply object-specific smoothing (using One Euro filtration) to the selected object. To do this:
Ensure that the newly created object is still selected.
Depending on whether you want to use an existing filtration type for this object, do one of the following:
If you want to use an existing filtration type, in the Object Type Preset section, select it from the dropdown list and save the object as described in step 9.
- If the required filtration type does not exist, in the Object Type Preset section, click Manage Presets and in the Object Presets dialog box, enter a name in the Create New Preset box and then click Add.
- In the Presets section, ensure the new preset is selected, then in the Smoothing section, change the Translation and Rotation properties as required.
- With Translation Beta set to zero, change the value of Translation Min Cut-Off to eliminate jitter during very slow movements.
Note that decreasing the value of Translation Min Cut-Off reduces jitter but increases lag.
- When you have finished adjusting the Translation Min Cut-Off value, increase the value of Translation Beta by very small increments to eliminate lag during faster movement.
Note that 0 = filtering on all translation motion; 1 = filtering on very slow translation motion only.
Follow the same procedure for adjusting the Rotation Min Cut-Off and Rotation Beta.
For detailed information on the One Euro filter and how to adjust these settings, visit www.lifl.fr/~casiez/1euro/.
- If you want Tracker to detect the object as static, select the Motion Model check box.
- When you have finished adjusting the properties, click Close.
- On the Objects tab, make sure that in the Object Type Preset section, the required filter is displayed for the selected object.
- As required, make the following optional changes:
- Left-click and drag the red, green, or blue axis lines emanating from the center of the object (translation manipulator) to translate the origin of the object to the desired position.
- Left-click the translation manipulator to toggle to a rotation manipulator.
- Drag the manipulator axes to orient the object to the desired pose.
- Modify the object's properties in the Properties pane. For more information, see Working with object properties.
- Save the object by right-clicking it the Objects list and selecting Save Object from the context menu.
Tracker saves the contents of the object in a .vsk file in the Objects folder.
Viewing unlabeled reconstructions requires additional processing, so for lowest output latency, when you have finished creating objects, ensure Track mode is selected. When Track mode is selected, the Track button is green.