1 files changed, 84 insertions, 0 deletions
diff --git a/gr-blocks/lib/stretch_ff_impl.cc b/gr-blocks/lib/stretch_ff_impl.cc
new file mode 100644
index 000000000..90bbc7ee5
--- /dev/null
+++ b/gr-blocks/lib/stretch_ff_impl.cc
@@ -0,0 +1,84 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2008,2010,2013 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 "stretch_ff_impl.h"
+#include <gr_io_signature.h>
+
+namespace gr {
+  namespace blocks {
+
+    stretch_ff::sptr
+    stretch_ff::make(float lo, size_t vlen)
+    {
+      return gnuradio::get_initial_sptr
+        (new stretch_ff_impl(lo, vlen));
+    }
+
+    stretch_ff_impl::stretch_ff_impl(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)
+    {
+    }
+
+    stretch_ff_impl::~stretch_ff_impl()
+    {
+    }
+
+    int
+    stretch_ff_impl::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;
+    }
+
+  } /* namespace blocks */
+} /* namespace gr */