The following steps describe typical labeling workflows. Note that the steps may vary depending on the capture, and alternative approaches could also be used. Utilize the reconstruction and auto-labeling pipelines in combination with the Labeling pane to best reconstruct and label the 3D data of your capture. From Motive 1.10 and above, standalone auto-labeling pipeline has been added, and it can be utilized to more efficiently and precisely label the markers.
Labeling Tips
Step 1. In the Project pane, Reconstruct and auto-label the take with all of the desired assets enabled.
Step 2. In the Timeline, examine the trajectories and navigate to the frame where labeling errors are frequent.
Step 3. Open the Labeling pane.
Step 4. Select an asset that you wish to label.
Step 5. From the label columns, Click on a marker label that you wish to re-assign.
Step 6. Inspect behavior of a selected trajectory and its labeling errors and set the appropriate labeling settings (allowable gap size, maximum spike and applied frame ranges).
Step 7. Switch to the QuickLabel mode (Hotkey: D).
Step 8. On the Perspective View, assign the labels onto the corresponding marker reconstructions by clicking on them.
Step 9. When all markers have been labeled, switch back to the Select Mode.
Step 1. Start with 2D data of a captured Take with model assets (skeletons and rigid bodies).
Step 2. Reconstruct and Auto-Label, or just Reconstruct, the Take with all of the desired assets enabled under the Project pane. If you use reconstruct only, you can skip step 3 and 5 for the first iteration.
Step 3. Examine the reconstructed 3D data, and inspect the frame range where markers are mislabeled.
Step 4. Using the Labeling pane, manually fix/assign marker labels, paying attention to your label settings (direction, max gap, max spike, selected duration).
Step 5. Unlabel all trajectories you want to re-auto-label.
Step 6. Auto-Label the Take again. Only the unlabeled markers will get re-labeled, and all existing labels will be kept the same.
Step 7. Re-examine the marker labels. If some of the labels are still not assigned correctly from any of the frames, repeat the steps 3-6 until complete.
The general process for resolving labeling error is:
For more data editing options, read through the Data Editing page.
When all markers are well reconstructing and there are no significant occlusions, you can just simply Reconstruct and Auto-label the Take to obtain 3D data and label all of the skeleton and rigid body markers. If reconstructed and auto-labeled 3D data is acceptable, you can proceed without post-processing.
When skeleton markers are mislabeled only within a specific frame range of the Take, you will have to manually re-label the markers during that range. This may occur when a subject performs dynamic movements or come into contact with another object during the recorded Take. After correcting the mislabeled markers, you can auto-label the take again to assign remaining missing labels.
Marker occlusions can be critical to the auto-labeling process. After having a gap for multiple frames, occluded markers can be unlabeled entirely, or nearby reconstructions can be mistakenly recognized as the occluded marker and result in labeling swaps or mislabels. Skeleton and rigid body asset definitions may accommodate labeling for such occlusions, but in some cases, labeling errors may persist throughout the Take. The following steps can be used to re-assign the labels in this case.
If tracked markers are relatively stationary during the occluded frames, you may want to increase the Maximum Marker Label Gap value under the Auto-Labeler settings in the Reconstruction pane to allow the occluded marker to maintain its label after auto-labeling the Take. However, note that adjusting this setting will not be useful if the marker is moving dynamically beyond the Prediction Radius (mm) settings during occlusion.
For Take(s) where skeletons are never perfectly tracked and the markers are consistently mislabeled, you will need to manually assign the correct labels for the skeleton asset(s). Situations like this could happen when the skeleton(s) are never in an easily trackable pose throughout the Take (e.g. captures where the actors are rolling on the ground). It is usually recommended that all skeleton ‘’Takes’’’ start and end with T-pose in order to easily distinguish the skeleton markers. This also helps the skeleton solver to correctly auto-label the associated markers; however, in some cases, only specific section of a Take needs be trimmed out, or including the calibration poses might not be possible. Manually assigning labels can help the auto-labeler to correctly label markers and have skeletons acquire properly in a Take. You will get best results if you manually label the entire skeleton, but doing so can be time consuming. You can also label only the mislabeled segment or the key segment (hip bone) and run the auto-labeler to see if it correctly assigns the labels with the small help.