Metrological characteristics of dual-tree complex wavelet transform for surface analysis

The metrological characteristics of a newly developed dual-tree complex wavelet transform (DT-CWT) for surface analysis are investigated, especially on the aspect of transmission characteristics analysis. The property of zero/linear phase by the DT-CWT ensures filtering results with no distortion and good ability for feature localization. Due to the 'steep transmission curve' property of the amplitude transmission characteristic, the DT-CWT can separate different frequency components efficiently. Both computer simulation and experimental results of practical surface 2D/3D filtering prove that the DT-CVVT filter is very suitable for the separation and extraction of frequency components such as surface roughness, waviness and form.