title: Use Python's Scipy DCT-II to do 2D or ND DCT
body: <p>I would like to use scipy's DCT-II since it is already coded and fast. Looking at the <a href="http://docs.scipy.org/doc/scipy/reference/generated/scipy.fftpack.dct.html" rel="noreferrer">doc</a>, it seems it is the 1D implementation. Is it possible to use it in such a way to use it as a 3D implementation? I'm not sure about the math. Are the 2D and 3D implementations the equivalent of multiplying 2 or 3 times the 1D using different dimensions in the calculation?</p>