I am developing a sound acquisition node with MEMS-Microphone and everything works fine(Windowing, Filtering..) except that the FFT output not as it's supposed to be! even it's work and frequencies in the input data is detected good, but imag != 0 why? and it seems that real doesn't represent the DC offset!
Thanks in advance!
I already use HPF with cut-off frequency ~10Hz and also try to average the PCM data before windowing&filtering but still approximately the same!Any suggestion?
no good result till now:( also, why the other frequency pins have a value?
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