Confidence value can be used to perform additional filtering of low confidence points. For every point in a dense point cloud the number of contributing combined depth maps is recorded and stored as a confidence value. Confidence is calculated only at the stage of building a dense point cloud, to save the value you need to enable Calculate point confidence in the Build Dense Cloud dialog window when starting the procedure:
To view confidence select Dense Cloud Confidence command on the Toolbar:
The color shows how many combined depth maps were used to create each point of a dense cloud.
Filtering by Confidence
Use the Filter by Confidence... command from the Tools > Dense Cloud menu to access the dialog box where minimum and maximum values for confidence range can be set:
The filtering results will be displayed in the Model view:
Note: Basically the Filter by Confidence (like other "filter by" commands) operation only hides the points in the Model view thus providing for more convenient navigation, display, and editing. The points can be removed manually should it be necessary, the feature does not remove the points automatically.
To remove low confidence points select point cloud in the Model view, using Select tools on the toolbar:
and delete points:
When the low confidence points are removed use Reset Filter command from the Tools > Dense Cloud menu to see the model:
Our kind thanks to Adolfo Bartolome Ibanez Vila Baukunst Arquitetura e Virtualização LTDA for sharing the dataset.