Second order Infinite Impulse Response filter. More...
Go to the source code of this file.
Functions | |
uint_t | aubio_filter_set_biquad (aubio_filter_t *f, lsmp_t b0, lsmp_t b1, lsmp_t b2, lsmp_t a1, lsmp_t a2) |
set coefficients of a biquad filter More... | |
aubio_filter_t * | new_aubio_filter_biquad (lsmp_t b0, lsmp_t b1, lsmp_t b2, lsmp_t a1, lsmp_t a2) |
create biquad filter with b0 , b1 , b2 , a1 , a2 coeffs More... | |
Second order Infinite Impulse Response filter.
This file implements a normalised biquad filter (second order IIR):
\( y[n] = b_0 x[n] + b_1 x[n-1] + b_2 x[n-2] - a_1 y[n-1] - a_2 y[n-2] \)
The filtfilt version runs the filter twice, forward and backward, to compensate the phase shifting of the forward operation.
See also Digital biquad filter on wikipedia.
Definition in file biquad.h.
uint_t aubio_filter_set_biquad | ( | aubio_filter_t * | f, |
lsmp_t | b0, | ||
lsmp_t | b1, | ||
lsmp_t | b2, | ||
lsmp_t | a1, | ||
lsmp_t | a2 | ||
) |
set coefficients of a biquad filter
f | filter object as returned by new_aubio_filter() |
b0 | forward filter coefficient |
b1 | forward filter coefficient |
b2 | forward filter coefficient |
a1 | feedback filter coefficient |
a2 | feedback filter coefficient |
create biquad filter with b0
, b1
, b2
, a1
, a2
coeffs
b0 | forward filter coefficient |
b1 | forward filter coefficient |
b2 | forward filter coefficient |
a1 | feedback filter coefficient |
a2 | feedback filter coefficient |