I understand the concept of the STFT. In order to avoid spectral leakage, you use a Hann window that overlaps by 50%. However, the problem that I have, is that the example code online does not account for this.
What I mean is, if the signal is overlapping by 50%, why doesn't anyone add the frequency content of the overlapping sections?
This is an example of what I mean. It looks like he is grabbing the overlap, but he is not adding the overlap pieces together. I don't see how the frequency content is being saved. He windows a function, does the FFT, then moves over and does the FFT again with the overlapping piece. I feel like he should be adding the overlapping pieces together. Is there something I am missing?
Thank you: John
Edit: I see the first answer, but it is still not hitting home. Hanning windows make the left and right information approach zero. So when it is overlapped, this removes this problem. However, when the FFT is taken, the information of the transform is put side-by-side. Wouldn't this mean, First Window=> upper time series information lower amplitude, Second window =>lower time series information lower amplitude.... This does not seem to solve the issue. You are still losing information with each window... is this not the case?