Imported Upstream version 3.2.2

[debian/gnuradio] / gnuradio-core / src / lib / general / gr_stretch_ff.cc

diff --git a/gnuradio-core/src/lib/general/gr_stretch_ff.cc b/gnuradio-core/src/lib/general/gr_stretch_ff.cc
new file mode 100644 (file)
index 0000000..f1822dc
--- /dev/null
+++ b/gnuradio-core/src/lib/general/gr_stretch_ff.cc
@@ -0,0 +1,74 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2008 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio 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, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gr_stretch_ff.h>
+#include <gr_io_signature.h>
+
+gr_stretch_ff_sptr
+gr_make_stretch_ff(float lo, size_t vlen)
+{
+  return gr_stretch_ff_sptr(new gr_stretch_ff(lo, vlen));
+}
+
+gr_stretch_ff::gr_stretch_ff(float lo, size_t vlen)
+  : gr_sync_block("stretch_ff",
+                 gr_make_io_signature(1, 1, vlen * sizeof(float)),
+                 gr_make_io_signature(1, 1, vlen * sizeof(float))),
+    d_lo(lo), d_vlen(vlen)
+{
+}
+
+int
+gr_stretch_ff::work(int noutput_items,
+                   gr_vector_const_void_star &input_items,
+                   gr_vector_void_star &output_items)
+{
+  const float *in  = (const float *) input_items[0];
+  float       *out = (float *) output_items[0];
+  
+  for (int count = 0; count < noutput_items; count++) {
+    float vmax = in[0] - d_lo;
+
+    for (unsigned int i = 1; i < d_vlen; i++) {
+      float vtmp = in[i] - d_lo;
+      if (vtmp > vmax)
+       vmax = vtmp;
+    }
+    
+    if (vmax != 0.0)
+      for (unsigned int i = 0; i < d_vlen; i++)
+       out[i] = d_lo * (1.0 - (in[i] - d_lo) / vmax);
+    else
+      for (unsigned int i = 0; i < d_vlen; i++)
+       out[i] = in[i];
+
+    in  += d_vlen;
+    out += d_vlen;
+  }
+  
+  return noutput_items;
+}
+