Asking about pre-processing step

[jack2805]

hello, I have a question regarding pre-processing.
I see you use the hrv.filter quotient library, can you explain where part you use the library?
the next question what pre-processing stages do you use? here I only saw cubic spline interpolation.
did you remove the noise? if so, what method did you use?
that's my question, i new to programming, I hope I can get the answer from you, thank you :)