Advanced filtering techniques

New standardized filters

Mountains® supports a wide range of filters for separating roughness and waviness frequencies or for extracting features at different scales. Available filters include the advanced Robust Gaussian, Spline and Morphological filters defined in the new ISO/TS 16610 standard. These new filters provide more flexibility and sometimes better separation between roughness and waviness than the older filters. However, the areal Gaussian filters is still a good choice for many applications.

Envelope filters

Morphological filters can be used in a lot of applications. A closing filter generates the upper envelope which is interesting in contact and wear assessment.

Form removal

Form is removed from a profile or surface using Least Square best fit of a predefined nominal shape or a polynomial. Form removal is required before any surface texture analysis.

FFT filters

For advanced analysis, Mountains® provides filters based on the edition of the Fourier spectrum.

Old 2CR filter (top); Gaussian filter (middle); Robust Gaussian filter (bottom).

Upper and lower envelopes with calculation of the enclosed area. (click to enlarge)

A least square cylinder removed from a cylinder bore measurement
to analyze its texture.

Old and new 2D filters available in MountainsMap®.