double FIgdelIIR (double w, const float h, int Nsec)
Calculate the group delay for a cascade IIR filter
This function calculates the group delay of an IIR filter specified by its
coefficients. The filter is a cascade of second order sections, with the
z-transform of the i'th filter section given as
h(i,0)*z^2 + h(i,1)*z + h(i,2)
H(i,z) = ------------------------------ .
z^2 + h(i,3)*z + h(i,4)
The group delay in seconds at frequency f for a filter with sampling
frequency Fs can be calculated as
gdelay = FIgdelIIR (2.0 * Pi * f / Fs, h, Nsec) / Fs .
-> double w
Normalized radian frequency (0 to Pi).
-> const float h
Array of filter coefficients for the filter sections. Each filter
section is defined by 5 filter coefficients.
-> int Nsec
Number of filter sections
Author / revision
/ Revision 1.6 2003/05/09
Main Index libtsp