SPATIAL FILTERING IN WAVE-VECTOR DOMAIN

Spatial data can be represented in the two-dimensional frequency domain. This simplifies the achievement of any desired transfer response in linear digital filter. Similar results are obtained approximately by convolution in space with a weighted coefficient set. The equivalence of wave-vector filtering and a special form of convolution filtering is demonstrated. The regional trend is rmoved from data prior to wave-vector filtering which gives one solution to problems arising at the edge of the data. A computationally convenient form of the two-dimensional fast Fourier transform is given for certain arrays.