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authormusil <tmusil@users.sourceforge.net>2012-09-06 15:54:46 +0000
committermusil <tmusil@users.sourceforge.net>2012-09-06 15:54:46 +0000
commit33dd6d603830640766aa1a5fe70137c856e2c145 (patch)
tree6e4a73f9100aec46971aa947a5f285c1d01ec35d /iemlib1/src/biquad_freq_resp.c
parent48cb10a8590255f952f53f3ff558ce345b86a3fe (diff)
other variable names, t_float to t_sample change, array access 64 bit
svn path=/trunk/externals/iemlib/; revision=16193
Diffstat (limited to 'iemlib1/src/biquad_freq_resp.c')
-rw-r--r--iemlib1/src/biquad_freq_resp.c46
1 files changed, 27 insertions, 19 deletions
diff --git a/iemlib1/src/biquad_freq_resp.c b/iemlib1/src/biquad_freq_resp.c
index 4fe9d31..aaadfac 100644
--- a/iemlib1/src/biquad_freq_resp.c
+++ b/iemlib1/src/biquad_freq_resp.c
@@ -1,7 +1,7 @@
/* For information on usage and redistribution, and for a DISCLAIMER OF ALL
* WARRANTIES, see the file, "LICENSE.txt," in this distribution.
-iemlib1 written by Thomas Musil, Copyright (c) IEM KUG Graz Austria 2000 - 2006 */
+iemlib1 written by Thomas Musil, Copyright (c) IEM KUG Graz Austria 2000 - 2011 */
#include "m_pd.h"
@@ -21,33 +21,39 @@ typedef struct _biquad_freq_resp
t_float b2;
t_outlet *x_out_re;
t_outlet *x_out_im;
+ t_outlet *x_out_abs;
+ t_outlet *x_out_arg;
} t_biquad_freq_resp;
static t_class *biquad_freq_resp_class;
static void biquad_freq_resp_float(t_biquad_freq_resp *x, t_floatarg freq_phase)
{
- t_float re1, im1, re2, im2;
- t_float c, s, a;
- t_float pi = 4.0f * atan(1.0f);
+ t_float re1, im1, re2, im2, re, im;
+ t_float c, s, ra;
+ t_float pi = 4.0 * atan(1.0);
- if(freq_phase < 0.0f)
- freq_phase = 0.0f;
- else if(freq_phase > 180.0f)
+ if(freq_phase < 0.0)
+ freq_phase = 0.0;
+ else if(freq_phase > 180.0)
freq_phase = 180.0;
freq_phase *= pi;
- freq_phase /= 180.0f;
+ freq_phase /= 180.0;
c = cos(freq_phase);
s = sin(freq_phase);
re1 = x->a0 + x->a1*c + x->a2*(c*c - s*s);
- im1 = x->a1*s + x->a2*2.0f*(s*c);
- re2 = 1.0f - x->b1*c - x->b2*(c*c - s*s);
- im2 = -x->b1*s - x->b2*2.0f*(s*c);
- a = re2*re2 + im2*im2;
- outlet_float(x->x_out_im, (re1*im2 - re2*im1)/a);/* because z^-1 = e^-jwt, negative sign */
- outlet_float(x->x_out_re, (re1*re2 + im1*im2)/a);
+ im1 = x->a1*s + x->a2*2.0*(s*c);
+ re2 = 1.0 - x->b1*c - x->b2*(c*c - s*s);
+ im2 = -x->b1*s - x->b2*2.0*(s*c);
+ ra = 1.0 / (re2*re2 + im2*im2);
+ im = (re1*im2 - re2*im1) * ra; /* because z^-1 = e^-jwt, negative sign */
+ re = (re1*re2 + im1*im2) * ra;
+ outlet_float(x->x_out_arg, 180.0*atan2(im, re)/pi);
+ outlet_float(x->x_out_abs, sqrt(re*re + im*im));
+ outlet_float(x->x_out_im, im);
+ outlet_float(x->x_out_re, re);
}
/* y/x = (a0 + a1*z-1 + a2*z-2)/(1 - b1*z-1 - b2*z-2);*/
@@ -69,11 +75,13 @@ static void *biquad_freq_resp_new(void)
t_biquad_freq_resp *x = (t_biquad_freq_resp *)pd_new(biquad_freq_resp_class);
x->x_out_re = outlet_new(&x->x_obj, &s_float);
x->x_out_im = outlet_new(&x->x_obj, &s_float);
- x->b1 = 0.0f;
- x->b2 = 0.0f;
- x->a0 = 0.0f;
- x->a1 = 0.0f;
- x->a2 = 0.0f;
+ x->x_out_abs = outlet_new(&x->x_obj, &s_float);
+ x->x_out_arg = outlet_new(&x->x_obj, &s_float);
+ x->b1 = 0.0;
+ x->b2 = 0.0;
+ x->a0 = 0.0;
+ x->a1 = 0.0;
+ x->a2 = 0.0;
return (x);
}