I'm relatively new to DSP and I'm currently investigating FIR filter and IIR filters. From what I've found FIR filters can be implemented efficiently using the overlap-save method, but I was wondering if it might be possible to do the same using a IIR zero-phase filter?
For example say I have a fairly long signal if I divided the signal into overlapping chunks similarly to how overlap-save does it, and I zero-phase filter each of these chunks to prevent phase distortions then discard the overlapping samples as per the algorithm, is there any way I would be able to end up with a consistent end result? I've been looking around the web and in books but I haven't been able to find any sources that says it's possible except for this site:
http://www.dsprelated.com/freebooks/sasp/Overlap_Add_OLA_STFT_Processing.html
Where it says for Zero-phase to overlap the segment with two of it's neighbors. I've tried experimenting with the instructions and attempted to implemented and used an overlapping low-pass zero-phase filter on a signal as seen below, with the overlap length being 150 on each end of the segments. I've also padded the borders of each segment with 0s to prevent border distortions. From the looks of the result I got it doesn't seem like that it'll be smooth however when I combine them compared to if I filtered it all in one go.
If anyone could give me some pointers on what I might be doing wrong and where I need to look further it'd be great thanks!