I am looking for a diagram (or pseudocode) for the Discrete Hartley Transform (DHT) for $N=8$ but cannot find anything. Since I am not a math major, cannot grasp the whole article.
Is there anyone who can draw the DHT diagram for $N=8$ or provide the algorithm or code, please?
US Patent 4,646,256 has everything you need:
https://patents.google.com/patent/US4646256/
download the PDF to see the tables and code aligned properly.
The patent calls it the Discrete Bracewell Transform and Fast Bracewell Transform, but it really is the DHT and FHT.