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-rw-r--r--iemlib1/src/sin_freq~.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/iemlib1/src/sin_freq~.c b/iemlib1/src/sin_freq~.c
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+/* 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 - 2011 */
+
+#include "m_pd.h"
+#include "iemlib.h"
+
+/* --- sin_freq~ - output the frequency of a --- */
+/* --- sinewave in Hz ----- */
+/* --- as a signal ----------------------------- */
+
+typedef struct _sin_freq_tilde
+{
+ t_object x_obj;
+ t_sample x_prev;
+ t_sample x_cur_out;
+ t_sample x_counter;
+ t_sample x_sr;
+ t_float x_float_sig_in;
+} t_sin_freq_tilde;
+
+static t_class *sin_freq_tilde_class;
+
+static t_int *sin_freq_tilde_perform(t_int *w)
+{
+ t_sample *in = (t_sample *)(w[1]);
+ t_sample *out = (t_sample *)(w[2]);
+ t_sin_freq_tilde *x = (t_sin_freq_tilde *)(w[3]);
+ int i, n = (t_int)(w[4]);
+ t_sample prev=x->x_prev;
+ t_sample cur_out=x->x_cur_out;
+ t_sample counter=x->x_counter;
+ t_sample sr=x->x_sr;
+ t_sample delta_x=0.0;
+
+ for(i=0; i<n; i++)
+ {
+ if((in[i] >= 0.0) && (prev < 0.0)) /* begin of counting, pos. zero cross of sig_in */
+ {
+ delta_x = prev / (prev - in[i]); /* dx = y1 / (y1 - y2) */
+ counter += delta_x;
+ cur_out = sr / counter;
+
+ counter = 1.0 - delta_x;
+ }
+ else
+ {
+ counter += 1.0;
+ }
+
+ prev = in[i];
+ out[i] = cur_out;
+ }
+
+ x->x_prev = prev;
+ x->x_cur_out = cur_out;
+ x->x_counter = counter;
+
+ return(w+5);
+}
+
+static void sin_freq_tilde_dsp(t_sin_freq_tilde *x, t_signal **sp)
+{
+ x->x_sr = (t_sample)sp[0]->s_sr;
+ dsp_add(sin_freq_tilde_perform, 4, sp[0]->s_vec, sp[1]->s_vec, x, sp[0]->s_n);
+}
+
+static void *sin_freq_tilde_new(void)
+{
+ t_sin_freq_tilde *x = (t_sin_freq_tilde *)pd_new(sin_freq_tilde_class);
+
+ outlet_new(&x->x_obj, &s_signal);
+
+ x->x_prev = 0.0;
+ x->x_cur_out = 0.0;
+ x->x_counter = 0.0;
+ x->x_sr = 44100.0;
+ x->x_float_sig_in = 0.0;
+
+ return (x);
+}
+
+void sin_freq_tilde_setup(void)
+{
+ sin_freq_tilde_class = class_new(gensym("sin_freq~"), (t_newmethod)sin_freq_tilde_new,
+ 0, sizeof(t_sin_freq_tilde), 0, 0);
+ CLASS_MAINSIGNALIN(sin_freq_tilde_class, t_sin_freq_tilde, x_float_sig_in);
+ class_addmethod(sin_freq_tilde_class, (t_method)sin_freq_tilde_dsp, gensym("dsp"), 0);
+}
+
+/*
+geradengleichung:
+
+y - y1 = ((y2 - y1) / (x2 - x1)) * (x - x1)
+y = ((y2 - y1) / (x2 - x1)) * (x - x1) + y1 = 0
+x1 = 0
+x2 = 1
+0 = ((y2 - y1) / 1) * (x) + y1
+-y1 = (y2 - y1) * x
+x = y1 / (y1 - y2)
+*/