[Ottverse] has an interesting series in progress to demystify video compression. The latest installment promises to explain discrete cosine transforms as though you were five years old.
We’ll be honest. At five, we probably didn’t know how to interpret this sentence:
…the Discrete Cosine Transform takes a set of N correlated (similar) data-points and returns N de-correlated (dis-similar) data-points (coefficients) in such a way that the energy is compacted in only a few of the coefficients M where M << N.
Still, the explanation is pretty clear and we really liked the analogy with the spheres and the stars in a constellation.