Apply an arbitrary Infinite Impulse Response filter.
It accepts the following parameters:
- z
-
Set numerator/zeros coefficients.
- p
-
Set denominator/poles coefficients.
- k
-
Set channels gains.
- dry_gain
-
Set input gain.
- wet_gain
-
Set output gain.
- f
-
Set coefficients format.
- tf
-
transfer function
- zp
-
Z-plane zeros/poles, cartesian (default)
- pr
-
Z-plane zeros/poles, polar radians
- pd
-
Z-plane zeros/poles, polar degrees
- r
-
Set kind of processing. Can be
d
- direct ors
- serial cascading. Defauls iss
. - e
-
Set filtering precision.
- dbl
-
double-precision floating-point (default)
- flt
-
single-precision floating-point
- i32
-
32-bit integers
- i16
-
16-bit integers
- response
-
Show IR frequency reponse, magnitude and phase in additional video stream. By default it is disabled.
- channel
-
Set for which IR channel to display frequency response. By default is first channel displayed. This option is used only when response is enabled.
- size
-
Set video stream size. This option is used only when response is enabled.
Coefficients in tf
format are separated by spaces and are in ascending
order.
Coefficients in zp
format are separated by spaces and order of coefficients
doesn’t matter. Coefficients in zp
format are complex numbers with i
imaginary unit.
Different coefficients and gains can be provided for every channel, in such case use ’|’ to separate coefficients or gains. Last provided coefficients will be used for all remaining channels.
Examples
-
Apply 2 pole elliptic notch at arround 5000Hz for 48000 Hz sample rate:
aiir=k=1:z=7.957584807809675810E-1 -2.575128568908332300 3.674839853930788710 -2.57512875289799137 7.957586296317130880E-1:p=1 -2.86950072432325953 3.63022088054647218 -2.28075678147272232 6.361362326477423500E-1:f=tf:r=d
-
Same as above but in
zp
format:aiir=k=0.79575848078096756:z=0.80918701+0.58773007i 0.80918701-0.58773007i 0.80884700+0.58784055i 0.80884700-0.58784055i:p=0.63892345+0.59951235i 0.63892345-0.59951235i 0.79582691+0.44198673i 0.79582691-0.44198673i:f=zp:r=s