- I'm doing the overlap-add method for STFT and I quite understand the implementation if it's a 50% overlap (where I add the 2nd half of the previous frame to the 1st half of the current frame during synthesis).
T1) [00,R1] T2) [R1,R2] ---> output sum of T1(R1)+T2(R1)
For a 75% overlap, my frame hops for 1/4 of the window length. So if I have a L=128 window size, my next frame moves onto the next R=32 samples. Now for the synthesis, my question is how many previous frames should I add for the current frame. From how I understand it should be 4, so is the figure below correct?
T1) [00,00,00,R1] T2) [00,00,R1,R2] T3) [00,R1,R2,R3] T4) [R1,R2,R3,R4] ---> output sum of T1(R1)+T2(R1)+T3(R1)+T4(R1)
- And how does the windowing functions work for a 75% overlap? I thought most windows like Hanning/Hamming work properly only for 50% overlap. What's the advantage of a 75% overlap then?