Skip to main content

Window Function (winfunc)

Signal processing window functions for reducing spectral leakage in FFT analysis.

API​

void winfunc_rectangular(float * taps, int n);
void winfunc_triangular(float * taps, int n);
void winfunc_flattop(float * taps, int n);
void winfunc_welch(float * taps, int n);
void winfunc_hanning(float * taps, int n);
void winfunc_hamming(float * taps, int n);
void winfunc_blackman(float * taps, int n);
void winfunc_kaiser(float * taps, int n, float beta);
  • winfunc_rectangular — Rectangular (uniform) window, no attenuation
  • winfunc_triangular — Triangular (Bartlett) window
  • winfunc_flattop — Flat-top window, optimized for amplitude accuracy
  • winfunc_welch — Welch (parabolic) window
  • winfunc_hanning — Hanning (raised cosine) window
  • winfunc_hamming — Hamming window, modified Hanning with non-zero endpoints
  • winfunc_blackman — Blackman window, higher side-lobe attenuation than Hanning/Hamming
  • winfunc_kaiser — Kaiser window with configurable beta parameter controlling the trade-off between main-lobe width and side-lobe attenuation

All functions fill taps array with n window coefficients. Apply window by multiplying sample data element-wise with the taps array before FFT.

Example​

int n = 1024;
float samples[n];
float window[n];

winfunc_hanning(window, n);

for(int i = 0; i < n; i++)
    samples[i] *= window[i];