Rotation Property of Discrete Fourier Transform for an image

image is rotated by some degree and its Spectrum is observed with respect to original image spectrum

Rotation property tells that if the image in the spatial domain is rotated by some amount then its spectrum which is obtained by DFT is also rotated by same amount. This is being showed with the example in .m file

f(m.n) as f(rcos θ,rsin𝝷)
Then DFT [f(rcos (θ+α),rsin (𝝷+𝞪)] = F [R cos (θ+α),R sin(𝝷+𝞪)]