Multiplicative complexity of the two-dimensional discrete Fourier transform DFT (2n; 2)

Shows that the two-dimensional discrete Fourier transform DFT (2 ⁿ; 2) can be transformed into a series of distinct second versions of the discrete cosine transform DCT. As a result of the minimal number of real multiplications over the field Q to compute the length 2ⁿ second version DCT, the authors derive the minimum number of real multiplications over the field Q necessary to compute a two-dimensional discrete Fourier transform for 2 ⁿ×2ⁿ real input data