1 files changed, 69 insertions, 0 deletions
diff --git a/gnuradio-runtime/lib/gr_sync_decimator.cc b/gnuradio-runtime/lib/gr_sync_decimator.cc
new file mode 100644
index 0000000000..a0f907db53
--- /dev/null
+++ b/gnuradio-runtime/lib/gr_sync_decimator.cc
@@ -0,0 +1,69 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004 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_sync_decimator.h>
+
+gr_sync_decimator::gr_sync_decimator (const std::string &name,
+				      gr_io_signature_sptr input_signature,
+				      gr_io_signature_sptr output_signature,
+				      unsigned decimation)
+  : gr_sync_block (name, input_signature, output_signature)
+{
+  set_decimation (decimation);
+}
+
+void
+gr_sync_decimator::forecast (int noutput_items, gr_vector_int &ninput_items_required)
+{
+  unsigned ninputs = ninput_items_required.size ();
+  for (unsigned i = 0; i < ninputs; i++)
+    ninput_items_required[i] = fixed_rate_noutput_to_ninput(noutput_items);
+}
+
+int
+gr_sync_decimator::fixed_rate_noutput_to_ninput(int noutput_items)
+{
+  return noutput_items * decimation() + history() - 1;
+}
+
+int
+gr_sync_decimator::fixed_rate_ninput_to_noutput(int ninput_items)
+{
+  return std::max(0, ninput_items - (int)history() + 1) / decimation();
+}
+
+int
+gr_sync_decimator::general_work (int noutput_items,
+				 gr_vector_int &ninput_items,
+				 gr_vector_const_void_star &input_items,
+				 gr_vector_void_star &output_items)
+{
+  int	r = work (noutput_items, input_items, output_items);
+  if (r > 0)
+    consume_each (r * decimation ());
+  return r;
+}
+