4. Wavelet frames

The continuous wavelet transform (3) , and the short-time Fourier transform (2) , are representations that are not "economical", in the sense that, starting from a one-dimensional signal, we arrive at a function of two real variables. These representations are said to be highly redundant. What's more, computer implementation of analysis and synthesis algorithms using these transformations requires signal sampling at some point. This is an argument in favor of working with discrete decompositions...