A novel low-complexity spatio-temporal ultra wide-angle polyphase cone filter bank applied to sub-pixel motion discrimination

A 3D ultra wide-angle cone-shaped filter pass band may be oriented to surround a 3D plane closely in 3D frequency space, thereby facilitating the selective filtering of 3D linear trajectory spatio-temporal signals. It is shown that the arithmetic complexity of discrete-domain versions of such wide-angle cone filters may be significantly reduced by employing a spatially-decimated 2D DFT-polyphase structure in the analysis and synthesis sections of a filter bank. The desired ultra wide-angle cone-shaped passband is approximated using first-order highly-selective 3D IIR frequency-planar (FP) filters in each band, between the analysis and synthesis sections. An application of this filter bank for the sub-pixel velocity discrimination of objects is described.