Polynomial transform fast Hartley transform

A fast algorithm for computing the two-dimensional discrete Hartley transform (2D-DHT) based on the polynomial transform is presented. Using a simple relation between the discrete Fourier transform (DFT), and the DHT it is found that the 2D-DHT can be mapped, by means of the polynomial transform, to a number of one-dimension type III discrete W transforms (DWT-III). An improved fast algorithm for computing the DWT-III is also proposed.