These structures takes input as normal order and shows output in bit reversed order.These structures can be obtained or solved by using butterfly diagram and its formulas.First we will break 8 point DFT into 4 points and then to 2 points IDFT.the formula of DITFFT's IDFT of 8 point is

X_m-1(p) = 1/2[X_m(p) + X_m(q)]

X_m-1(q) = 1/2W_n^-r[X_m(p) - X_m(q)]

Enter the input sequence :

Submit for idft ditfft 8 point

4 point IDFT of DITFFT

This 4 point IDFT of DITFFT is same as 8 point DITFFT but here we will just break 4 point IDFT into 2 points IDFT by using the same butterfly diagram and the above formulas.

Enter the input sequence :

Submit for idft ditfft 4 point