1 files changed, 77 insertions, 0 deletions
diff --git a/gr-blocks/lib/rms_ff_impl.cc b/gr-blocks/lib/rms_ff_impl.cc
new file mode 100644
index 000000000..2b8cdc34e
--- /dev/null
+++ b/gr-blocks/lib/rms_ff_impl.cc
@@ -0,0 +1,77 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2005,2010,2013 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 "rms_ff_impl.h"
+#include <gr_io_signature.h>
+#include <cmath>
+
+namespace gr {
+  namespace blocks {
+
+    rms_ff::sptr
+    rms_ff::make(double alpha)
+    {
+      return gnuradio::get_initial_sptr
+        (new rms_ff_impl(alpha));
+    }
+
+    rms_ff_impl::rms_ff_impl(double alpha)
+      : gr_sync_block("rms_ff",
+                      gr_make_io_signature(1, 1, sizeof(float)),
+                      gr_make_io_signature(1, 1, sizeof(float))),
+        d_iir(alpha)
+    {
+    }
+
+    rms_ff_impl::~rms_ff_impl()
+    {
+    }
+
+    void
+    rms_ff_impl::set_alpha(double alpha)
+    {
+      d_iir.set_taps(alpha);
+    }
+
+    int
+    rms_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 i = 0; i < noutput_items; i++) {
+        double mag_sqrd = in[i]*in[i];
+        double f = d_iir.filter(mag_sqrd);
+        out[i] = sqrt(f);
+      }
+
+      return noutput_items;
+    }
+
+  } /* namespace blocks */
+} /* namespace gr */