1 files changed, 92 insertions, 0 deletions
diff --git a/flib/src/trist~.c b/flib/src/trist~.c
new file mode 100644
index 0000000..93fd3b9
--- /dev/null
+++ b/flib/src/trist~.c
@@ -0,0 +1,92 @@
+/* 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 tristimulus of one frame according to method outlined by Pollard and Jansson. First argument determines method used (x,y, or z) */
+
+#include "flib.h"
+static t_class *trist_class;
+
+typedef struct _trist {
+  t_object  x_obj;
+  t_float f,x;
+  t_symbol *t;
+} t_trist;
+
+static t_int *trist_perform(t_int *w)
+{
+  t_sample *in = (t_sample *)(w[1]);
+  t_trist *x = (t_trist *)(w[2]);
+  t_int N = (t_int)(w[3]),M = (N >> 1) - 1,n,i = 0;
+  t_float T, A = 0,p1 = 0,p2 = 0,p3 = 0,p4 = 0,p5 = 0;
+
+  for(n = 0; n < M; n++){
+	  A += in[n];
+	  if (in[n] != 0 && i < 5){
+		  switch(i){
+			  case 4: p5 = in[n]; i++; 
+					  break;
+			  case 3: p4 = in[n]; i++;
+					  break;
+			  case 2: p3 = in[n]; i++;
+					  break;
+			  case 1: p2 = in[n]; i++;
+					  break;
+			  case 0: p1 = in[n]; i++;
+					  break;
+		  }
+	  }
+  }
+  if (*x->t->s_name == 'z')
+	  T = p1 / A;
+	  else if (*x->t->s_name == 'y')
+		  T = (p2 + p3 + p4) / A;
+		  else
+			  T = (A - p1 + p2 + p3 + p4 + p5) / A;
+
+  outlet_float(x->x_obj.ob_outlet, T);
+  return (w+4);
+}
+
+static void trist_dsp(t_trist *x, t_signal **sp)
+{
+  dsp_add(trist_perform, 3,
+          sp[0]->s_vec, x, sp[0]->s_n);
+}
+
+static void *trist_new(t_symbol *s)
+{
+  t_trist *x = (t_trist *)pd_new(trist_class);
+  x->t = s;
+  outlet_new(&x->x_obj, &s_float);
+  return (void *)x;
+}
+
+
+void trist_tilde_setup(void) {
+  trist_class = class_new(gensym("trist~"),
+        (t_newmethod)trist_new,
+        0, sizeof(t_trist),
+        CLASS_DEFAULT, A_DEFSYMBOL, 0);
+
+  class_addmethod(trist_class,
+        (t_method)trist_dsp, gensym("dsp"), 0);
+  CLASS_MAINSIGNALIN(trist_class, t_trist,f);
+  class_sethelpsymbol(trist_class, gensym("help-flib"));
+}