2017

To define real world units in your analyzed scene:
1 In the Real World Measures section of the Fine Tuning tab, enable Define.
2 Select a point in the image, then press Alt and select a second point.
A red line is drawn between the two points.
3 Disable Define.
4 In the Length field, enter a measurement of the length between the two points, in the unit of your
choice (centimeters, inches, etc.). The Action scene scales to the distance you enter.
If you export the point cloud through the 3D camera, you'll be able to specify the unit of measurement
in the
Export Camera menu (page 642).
Setting the Orientation
Although it is not mandatory to define a ground plane in your image, it helps orient the reconstruction of
the cameras.
To define the camera track ground plane:
1 In the Plane section, enable Define.
NOTE If you selected Pan and Tilt as the camera type (or if the Auto Detect switched to Pan and Tilt) the
Plane Define button is not available. The rest of the settings in this group are still available, but only for
orientation purposes.
2 Select a minimum of three points in the image that represent the plane of the X/Z axes, such as the
ground, a table, or any flat surface.
The selected points appear as red squares with white crosses.
TIP You may want to disable the tracker temporarily and point display options (or raise the transparency
level) to help you find and select the plane points.
3 Use the Position and Rotation controls to define the orientation of the ground plane.
4 Use the Scale field to specify the scale of the scene.
5 Disable Define.
Filtering Trackers to Fine Tune the Track Analysis
Use the Filter settings to delete lower quality trackers.
660 | Chapter 15 Compositing in 3D Space with Action