diff options
Diffstat (limited to 'src/iemlib1/biquad_freq_resp.c')
-rw-r--r-- | src/iemlib1/biquad_freq_resp.c | 186 |
1 files changed, 93 insertions, 93 deletions
diff --git a/src/iemlib1/biquad_freq_resp.c b/src/iemlib1/biquad_freq_resp.c index cda16c6..f572cd7 100644 --- a/src/iemlib1/biquad_freq_resp.c +++ b/src/iemlib1/biquad_freq_resp.c @@ -1,93 +1,93 @@ -/* 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 - 2005 */
-
-#ifdef NT
-#pragma warning( disable : 4244 )
-#pragma warning( disable : 4305 )
-#endif
-
-
-#include "m_pd.h"
-#include "iemlib.h"
-#include <math.h>
-#include <stdio.h>
-#include <string.h>
-
-/* ------------------------ biquad_freq_resp ------------------- */
-/* -- calculates the frequency responce of a biquad structure -- */
-
-typedef struct _biquad_freq_resp
-{
- t_object x_obj;
- float a0;
- float a1;
- float a2;
- float b1;
- float b2;
- t_outlet *x_out_re;
- t_outlet *x_out_im;
-} t_biquad_freq_resp;
-
-static t_class *biquad_freq_resp_class;
-
-static void biquad_freq_resp_float(t_biquad_freq_resp *x, t_float f)
-{
- float re1, im1, re2, im2;
- float c, s, a;
-
- if(f < 0.0f)
- f = 0.0f;
- else if(f > 180.0f)
- f = 180.0;
- f *= 3.14159265f;
- f /= 180.0f;
-
- c = cos(f);
- s = sin(f);
-
- 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);
-
-}
-/* y/x = (a0 + a1*z-1 + a2*z-2)/(1 - b1*z-1 - b2*z-2);*/
-
-static void biquad_freq_resp_list(t_biquad_freq_resp *x, t_symbol *s, int argc, t_atom *argv)
-{
- if((argc == 5)&&IS_A_FLOAT(argv,4)&&IS_A_FLOAT(argv,3)&&IS_A_FLOAT(argv,2)&&IS_A_FLOAT(argv,1)&&IS_A_FLOAT(argv,0))
- {
- x->b1 = (float)atom_getfloatarg(0, argc, argv);
- x->b2 = (float)atom_getfloatarg(1, argc, argv);
- x->a0 = (float)atom_getfloatarg(2, argc, argv);
- x->a1 = (float)atom_getfloatarg(3, argc, argv);
- x->a2 = (float)atom_getfloatarg(4, argc, argv);
- }
-}
-
-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;
- return (x);
-}
-
-void biquad_freq_resp_setup(void)
-{
- biquad_freq_resp_class = class_new(gensym("biquad_freq_resp"), (t_newmethod)biquad_freq_resp_new, 0,
- sizeof(t_biquad_freq_resp), 0, 0);
- class_addfloat(biquad_freq_resp_class, biquad_freq_resp_float);
- class_addlist(biquad_freq_resp_class, (t_method)biquad_freq_resp_list);
- class_sethelpsymbol(biquad_freq_resp_class, gensym("iemhelp/help-biquad_freq_resp"));
-}
+/* 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 - 2005 */ + +#ifdef NT +#pragma warning( disable : 4244 ) +#pragma warning( disable : 4305 ) +#endif + + +#include "m_pd.h" +#include "iemlib.h" +#include <math.h> +#include <stdio.h> +#include <string.h> + +/* ------------------------ biquad_freq_resp ------------------- */ +/* -- calculates the frequency responce of a biquad structure -- */ + +typedef struct _biquad_freq_resp +{ + t_object x_obj; + float a0; + float a1; + float a2; + float b1; + float b2; + t_outlet *x_out_re; + t_outlet *x_out_im; +} t_biquad_freq_resp; + +static t_class *biquad_freq_resp_class; + +static void biquad_freq_resp_float(t_biquad_freq_resp *x, t_float f) +{ + float re1, im1, re2, im2; + float c, s, a; + + if(f < 0.0f) + f = 0.0f; + else if(f > 180.0f) + f = 180.0; + f *= 3.14159265f; + f /= 180.0f; + + c = cos(f); + s = sin(f); + + 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); + +} +/* y/x = (a0 + a1*z-1 + a2*z-2)/(1 - b1*z-1 - b2*z-2);*/ + +static void biquad_freq_resp_list(t_biquad_freq_resp *x, t_symbol *s, int argc, t_atom *argv) +{ + if((argc == 5)&&IS_A_FLOAT(argv,4)&&IS_A_FLOAT(argv,3)&&IS_A_FLOAT(argv,2)&&IS_A_FLOAT(argv,1)&&IS_A_FLOAT(argv,0)) + { + x->b1 = (float)atom_getfloatarg(0, argc, argv); + x->b2 = (float)atom_getfloatarg(1, argc, argv); + x->a0 = (float)atom_getfloatarg(2, argc, argv); + x->a1 = (float)atom_getfloatarg(3, argc, argv); + x->a2 = (float)atom_getfloatarg(4, argc, argv); + } +} + +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; + return (x); +} + +void biquad_freq_resp_setup(void) +{ + biquad_freq_resp_class = class_new(gensym("biquad_freq_resp"), (t_newmethod)biquad_freq_resp_new, 0, + sizeof(t_biquad_freq_resp), 0, 0); + class_addfloat(biquad_freq_resp_class, biquad_freq_resp_float); + class_addlist(biquad_freq_resp_class, (t_method)biquad_freq_resp_list); + class_sethelpsymbol(biquad_freq_resp_class, gensym("iemhelp/help-biquad_freq_resp")); +} |