Review occlusion fixing

When you import an .mcp file or perform any processing that includes occlusion fixing, your first step is to review it to ensure that it is labeled correctly and that the automatic occlusion fixing worked well.

To review occlusion fixing in Shogun Post, both of the following (default) settings must be selected:

• In Shogun Live: Before capture, in the General section of the Processing panel, Occlusion Fixing must be selected.
  
  
  
  This normally produces higher quality results, especially during occlusion-heavy moves such as interactions and when a subject is on the edge of the volume. Occlusion fixing is stored as a layer when the .mcp data is recorded.

• In Shogun Post: Before importing the .mcp file that was captured with Occlusion Fixing selected as described above, in the Preferences dialog box (General > Preferences), on the File Import tab, in the File Format field, select MCP File and ensure Apply Fixed Markers is selected.
  
  

You can then compare the data before and after occlusion fixing in a 3D Scene view (or any other 3D view) in Post.

Note that, by default, in the 3D Scene view Show All Clips is selected:

This is necessary to enable you to view data from the backup clip, which contains the data before occlusion fixing, as well as the current (occlusion-fixed) clip.

Before you start your review, ensure you can recognize the various types of data that may be displayed in the 3D Scene view, as listed in the following table.

Symbol in 3D view	Description	Data type
	Circle	Original labeled markers from the backup clip. Displayed by default if the difference between the position of the original marker and the occlusion-fixed marker is greater than 1 cm.
	Sphere	Markers without gaps
	Sphere with a dot in the center	Markers that have been occlusion-fixed during a gap
	Sphere with a cross in the center	Markers that have had a gap manually filled
	Red sphere	Markers that are missing at the current frame
	Wireframe box	Constraint, showing expected location of marker

If circles are displayed for some markers during some time ranges, it indicates that the marker position was changed by more than 1 cm by occlusion fixing.

In this case, check the position of the occlusion-fixed marker. If it doesn’t look right, the cause is likely to be either a labeling mistake or an occlusion-fixing error. To fix these problems, see Correcting labeling mistakes.

Correcting labeling mistakes

If you notice any swaps, mis-labels or other issues with marker data and the file has already been occlusion fixed, the recommended workflow is to restore the data back to its original state before it was occlusion-fixed.

You can do this on a per subject basis using the Restore section of the Marker Editing panel. Normally, restore the data across the whole take, because occlusion fixing across a range leads to jumps in the data.

The recommended workflow for dealing with problematic occlusion-fixed data is:

1. From the Current Subject chooser, select the required subject, or if you want to work on everything, select All.

2. In the Restore section of the Marker Editing panel, with selected subject active, select Restore All Data.
   
   
   
   

3. Fix any labeling issues that are present in your data. For more information, see Use the Labeling panel in Clean up data and Fix common labeling issues.
4. Re-run occlusion fixing from the Processing panel.
5. Re-run Solve Solving to update the solving skeletons.