The discrete Hartley transform has been proposed as an alternative tool suitable for DFT referring real data and has been used in many signal and image processing applications.Because the existed algorithms for three-dimension discrete Hartley transform(3-D DHT)only can compute sequences whose lengths are the

m

th power of 2(

m

is an integer)

this paper proposes a novel split-radix-2/4 algorithm for the fast computation of 3-D DHT

which provides more flexibility in selecting the sequence length.Moreover

it achieves a large reduction in computational complexity compared to computing by zero padding.