TY - JOUR N2 - The form, waviness and roughness components of a measured profile are separated by means of digital filters. The aim of analysis was to develop an algorithm for one-dimensional filtering of profiles using approximation by means of B-splines. The theory of B-spline functions introduced by Schoenberg and extended by Unser et al. was used. Unlike the spline filter proposed by Krystek, which is described in ISO standards, the algorithm does not take into account the bending energy of a filtered profile in the functional whose minimization is the principle of the filter. Appropriate smoothness of a filtered profile is achieved by selecting an appropriate distance between nodes of the spline function. In this paper, we determine the Fourier transforms of the filter impulse response at different impulse positions, with respect to the nodes. We show that the filter cutoff length is equal to half of the node-to-node distance. The inclination of the filter frequency characteristic in the transition band can be adjusted by selecting an appropriate degree of the B-spline function. The paper includes examples of separation of 2D roughness, as well as separation of form and waviness of roundness profiles. L1 - http://journals.pan.pl/Content/90315/PDF/Journal10178-VolumeXXII%20Issue2_10paper.pdf.pdf L2 - http://journals.pan.pl/Content/90315 PY - 2015 IS - No 2 EP - 302 DO - 10.1515/mms-2015-0016 KW - profile filtering KW - B-spline functions KW - roundness KW - roughness A1 - Janecki, Dariusz A1 - Cedro, Leszek A1 - Zwierzchowski, Jarosław PB - Polish Academy of Sciences Committee on Metrology and Scientific Instrumentation VL - vol. 22 DA - 2015[2015.01.01 AD - 2015.12.31 AD] T1 - Separation Of Non-Periodic And Periodic 2D Profile Features Using B-Spline Functions SP - 289 UR - http://journals.pan.pl/dlibra/publication/edition/90315 T2 - Metrology and Measurement Systems ER -