Points > Reduce Noise compensates for scanner error (“noise”) by moving points to statistically correct locations. Noise can make sharp edges dull and make smooth curves rough. The result is a more uniform arrangement of points that can be wrapped more smoothly. A color-coded representation of the point movement is available.
Typically, use Reduce Noise after removing outliers and portions of a scan that are not part of the object (such as a tabletop), and before the various forms of Sampling.
Reduce Noise works better on surface scans than on volumetric point sets.
Parameters group - customizes the operation based on the type of the noisy object.
Free-form shapes radio button - If the object represents a free-form or organic shape, this reduces the noise with respect to surface curvature. This is an aggressive reduction technique.
Prismatic Shapes (conservative) radio button - helps maintain sharpness of features such as edges on a mechanical or angular shape.
Prismatic Shapes (aggressive) radio button - helps maintain sharpness of features such as edges on a mechanical or angular shape.
Smoothness Level slider (five levels from None to Max) - specifies the aggressiveness of point detection. Generally, use the lowest setting that gives acceptable results.
Iterations integer field (1 to 5; applies to unordered point objects and polygon objects only) - specifies the number of noise reduction passes.
Deviation Limit input box - specifies the maximum distance that a point is allowed to move.
Outliers checkbox - (only for unordered point objects; not when the Preview checkbox is checked) specifies special treatment for points that are especially far from the surface.
Threshold field - specifies that points beyond a given distance are ignored, and not moved during the noise reduction process.
Select - leaves outliers in the selected state after the dialog is closed.
Delete - deletes points that are found beyond the Threshold.
Include Isolated Points checkbox - An isolated point is an outlier that is so far from the object that it is never subject to noise reduction (regardless of the Limit value). This checkbox specifies whether isolated points are subject to the Select and Delete radio buttons.
Preview checkbox - (only for unordered point objects) displays the anticipated effects of a noise reduction process.
Preview Points input field - specifies the number of points to be used to generate the preview.
Sampling checkbox and field - specifies the minimum distance between points in the preview.
Display Deviations group - controls the color-coded graphical representation of the noise reduction.
Spectrum Name dropdown - “Result” means that the deviation spectrum is automatically scaled to represent the result of this Reduce Noise function. Other names represent customized deviation spectrums that were created by Analysis > Edit Spectrum.
See All About Spectrums.
Statistics group - indicates the distances that points were moved during noise reduction.
Maximum Distance - the greatest distance that any point was moved.
Average Distance - the average distance that all points were moved.
Standard Deviation - describes the variability of the distances.
Crease Info button - displays the crease angle. This predicts the success of Points > Wrap. A value greater than 10 suggests that additional noise reduction or sampling is necessary.
OK button - reduces noise, saves the object to the Model Manager, and terminates the dialog.
Apply button - reduces noise and leaves the dialog open.
Cancel button - terminates the dialog without saving the noise-reduced object to the Model Manager.