# Tag Info

If you have a function $f \left[ m, n \right] \in \mathbb{R}^{M \times N}$ then the DFT of those functions is an orthogonal basis of functions in $\mathbb{C}^{M \times N}$. So if we have:  F \left[ k , l \right] = \frac{1}{\sqrt{M N}} \sum_{m = 0}^{M - 1} \sum_{n = 0}^{N - 1} f \left[ m, n \right] {e}^{-j 2 \pi \left( \frac{k}{M} m + \frac{l}{N} n \...