Matrix Expansions for Computing the Discrete Hartley Transform for blocklength N=0 (mod 4)
A new fast algorithm for computing the discrete Hartley transform (DHT) is presented,
which is based on the expansion of the transform matrix.
The algorithm presents a better performance, in terms of multiplicative complexity,
than previously known fast Hartley transform algorithms and same
performance, in terms of additive complexity, than Split-Radix algorithm.
A detailed description of the computation of DHTs with blocklengths 8 and 16 is shown.
The algorithm is very attractive for blocklengths N > 128.