Areal Filtering Methods

Filtering is essential for surface texture characterisation. FiltrationFiltration separates the measured data into different scales of interest. The extracted scales can be characterised by parameters given in ISO 25178 part 2. In this chapter the three areal filtering standards, ISO 16610 part 61 (areal Gaussian filters), ISO 16610 part 62 (areal spline filters) and ISO 16610 part 71 (robust areal Gaussian regression filters), are discussed. Morphological filters and multi-resolution analyses are also briefly introduced.