1 files changed, 75 insertions, 0 deletions
diff --git a/flib/src/sfm~.c b/flib/src/sfm~.c
new file mode 100644
index 0000000..ee745c2
--- /dev/null
+++ b/flib/src/sfm~.c
@@ -0,0 +1,75 @@
+/* flib - PD library for feature extraction 
+Copyright (C) 2005  Jamie Bullock
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+
+
+/* calculates spectral flatness measure as described by Tae Hong Park*/
+
+#include "m_pd.h"
+#include <math.h>
+
+static t_class *sfm_class;
+
+typedef struct _sfm {
+  t_object  x_obj;
+  t_float f,x;
+} t_sfm;
+
+static t_int *sfm_perform(t_int *w)
+{
+  t_sample *in = (t_sample *)(w[1]);
+  t_sfm *x = (t_sfm *)(w[2]);
+  t_int N = (t_int)(w[3]),M = (N >> 1) - 1,n;
+  t_float F, A = 0, G = 1;
+  t_float iM = 1 / (float)M;
+  for(n = 0; n < M; n++){
+	  if(in[n] !=0){
+		  G *= in[n];
+	      A += in[n];
+	  }
+  }
+  F = 10 * log10(pow(G, iM) / (iM * A));
+  outlet_float(x->x_obj.ob_outlet, F);
+  return (w+4);
+}
+
+static void sfm_dsp(t_sfm *x, t_signal **sp)
+{
+  dsp_add(sfm_perform, 3,
+          sp[0]->s_vec, x, sp[0]->s_n);
+}
+
+static void *sfm_new(void)
+{
+  t_sfm *x = (t_sfm *)pd_new(sfm_class);
+  outlet_new(&x->x_obj, &s_float);
+  return (void *)x;
+}
+
+
+void sfm_tilde_setup(void) {
+  sfm_class = class_new(gensym("sfm~"),
+        (t_newmethod)sfm_new,
+        0, sizeof(t_sfm),
+        CLASS_DEFAULT,0);
+
+  class_addmethod(sfm_class,
+        (t_method)sfm_dsp, gensym("dsp"), 0);
+  CLASS_MAINSIGNALIN(sfm_class, t_sfm,f);
+  class_sethelpsymbol(sfm_class, gensym("help-flib"));
+}