1 files changed, 112 insertions, 0 deletions
diff --git a/src/dfreq~.c b/src/dfreq~.c
new file mode 100644
index 0000000..7016784
--- /dev/null
+++ b/src/dfreq~.c
@@ -0,0 +1,112 @@
+/******************************************************
+ *
+ * zexy - implementation file
+ *
+ * copyleft (c) IOhannes m zmölnig
+ *
+ *   1999:forum::für::umläute:2004
+ *
+ *   institute of electronic music and acoustics (iem)
+ *
+ ******************************************************
+ *
+ * license: GNU General Public License v.2
+ *
+ ******************************************************/
+
+#include <stdio.h>
+
+#include "zexy.h"
+
+/* ------------------------ dspobj~ ----------------------------- */
+
+/* datendefinition */
+
+static t_class *dfreq_class;
+
+typedef struct _dfreq
+{
+  t_object x_obj;
+
+  t_float freq;  /*freqenz variable */
+  t_float alt;
+  float sampcount;
+  t_float sr;
+} t_dfreq;
+
+
+static t_int *dfreq_perform(t_int *w)
+{
+  t_float *in = (t_float *)(w[1]);
+  t_float *out = (t_float *)(w[2]);
+  int n = (int)(w[3]);
+  t_dfreq *x = (t_dfreq *) w[4];
+
+  t_float a = x->alt, c = x->sampcount;
+  t_float freq = x->freq, sr=x->sr;
+
+  t_float delta_inv;
+
+  while (n--) {
+
+    if( (a * *in) < 0 && (a < *in)){
+
+	/* interpolate for real zerocross */
+	  delta_inv = 1./(*in-a);
+      if(c > 0.0)
+		  freq = sr / ((t_float) c + a*delta_inv);
+      else
+		  freq = sr;
+
+      c = *in*delta_inv; /*rest of time */
+    };
+
+    a = *in;
+    in++;
+    c += 1.0;
+    *out++ = freq;
+  }
+
+  x->alt = a;  
+  x->sampcount = c;
+  x->freq=freq;
+
+  return (w+5);
+}
+
+static void dfreq_dsp(t_dfreq *x, t_signal **sp)
+{
+    dsp_add(dfreq_perform, 4, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n,x);
+}
+
+
+
+static void *dfreq_new(void)
+{
+  t_dfreq *x = (t_dfreq *)pd_new(dfreq_class);
+  outlet_new(&x->x_obj, gensym("signal"));
+
+  x->sr = sys_getsr();
+
+  return (x);
+}
+
+static void helper(void)
+{
+	post("\n%c dfreq~\t :: pitch-detector that counts zero-crossings", HEARTSYMBOL);
+	post("\noutputs a frequency estimate as a stream~ that will be updated every zero-X");
+	post("\ncreation::\t'dfreq~': that's all");
+}
+
+
+void dfreq_tilde_setup(void)
+{
+    dfreq_class = class_new(gensym("dfreq~"), (t_newmethod)dfreq_new, 0,
+    	sizeof(t_dfreq), 0, A_NULL);
+    class_addmethod(dfreq_class, nullfn, gensym("signal"), 0);
+    class_addmethod(dfreq_class, (t_method)dfreq_dsp, gensym("dsp"), 0);
+
+	class_addmethod(dfreq_class, (t_method)helper, gensym("help"), 0);
+	class_sethelpsymbol(dfreq_class, gensym("zexy/dfreq~"));
+  zexy_register("dfreq~");
+}