# How to interpolate complex array (FT)?

I do Fourier Transform for an image, then consider line(slice) in FFT image. When that slice isn't parallel neither x- not y-axis, coordinates are not integer. E.g. slice can hold indices {(0,0), (0.25,1), (0.5,2), (0.75,3), (1,4)...}. When using nearest-interpolation, quality of whatever I do is pure.

What techniques can you suggest to improve interpolation in Fourier grid?

• Welcome to DSP.SE! I'm not sure what you mean by "When using nearest-interpolation, quality of whatever I do is pure." Could you rephrase it?
– Peter K.
Sep 25, 2015 at 16:26
• @Peter K. : I want to calculate invertible Radon transform using Projection-Slice theorem. So, when for point (0.75, 3) use value at (1,3), and then perform inverse transform, reconstruction is not perfect.
– olha
Sep 25, 2015 at 16:33
• Are all your coordinates multiples of 0.25 or such? Sep 26, 2015 at 7:19