Digital Metrology Notepad Series - The Gaussian Filter

When you're driving, your tires, shock absorbers, and suspension remove most of the harsh vibrations from the road, leaving you with a smooth ride.
In surface texture analysis, filtering has much the same effect: separating larger surface structures (the "waviness") from the finer "roughness." There are several types of filters available to accomplish this. The most common filter is the Gaussian filter, which passes a special kind of moving average through the data to determine the waviness. The Gaussian filter acts like the perfect shock absorber in terms of separating waviness and roughness...but it does have nuances. In this video we show how the Gaussian filter works, and we show some details you need to understand in order to decide when and how to use this filter type.
While the Gaussian might be the mathematically “perfect” filter for separating wavelengths, it does have problems for surfaces with plateaus and/or extreme features. For those surfaces, be sure to check out our Fake Peaks & Filters notepad: • Fake Peaks and Filters .