1 files changed, 79 insertions, 0 deletions
diff --git a/src/utils/scale.c b/src/utils/scale.c
new file mode 100644
index 0000000..3bd116c
--- /dev/null
+++ b/src/utils/scale.c
@@ -0,0 +1,79 @@
+/*
+  Copyright (C) 2003-2009 Paul Brossier <piem@aubio.org>
+
+  This file is part of aubio.
+
+  aubio 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 3 of the License, or
+  (at your option) any later version.
+
+  aubio 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 aubio.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+#include "aubio_priv.h"
+#include "fvec.h"
+#include "utils/scale.h"
+
+struct _aubio_scale_t {
+  smpl_t ilow;
+  smpl_t ihig;
+  smpl_t olow;
+  smpl_t ohig;
+
+  smpl_t scaler;
+  smpl_t irange;
+
+  /* not implemented yet : type in/out data
+     bool inint;
+     bool outint;
+     */
+};
+
+aubio_scale_t * new_aubio_scale (smpl_t ilow, smpl_t ihig,
+    smpl_t olow, smpl_t ohig) {
+  aubio_scale_t * s = AUBIO_NEW(aubio_scale_t);
+  aubio_scale_set_limits (s, ilow, ihig, olow, ohig);
+  return s;
+}
+
+void del_aubio_scale(aubio_scale_t *s) {
+  AUBIO_FREE(s);
+}
+
+uint_t aubio_scale_set_limits (aubio_scale_t *s, smpl_t ilow, smpl_t ihig,
+    smpl_t olow, smpl_t ohig) {
+  smpl_t inputrange = ihig - ilow;
+  smpl_t outputrange= ohig - olow;
+  s->ilow = ilow;
+  s->ihig = ihig;
+  s->olow = olow;
+  s->ohig = ohig;
+  if (inputrange == 0) {
+    s->scaler = 0.0;
+  } else {
+    s->scaler = outputrange/inputrange;
+    if (inputrange < 0) {
+      inputrange = inputrange * -1.0f;
+    }
+  }
+  return AUBIO_OK;
+}
+
+void aubio_scale_do (aubio_scale_t *s, fvec_t *input) 
+{
+  uint_t j;
+  for (j=0;  j < input->length; j++){
+    input->data[j] -= s->ilow;
+    input->data[j] *= s->scaler;
+    input->data[j] += s->olow;
+  }
+}
+