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+/* -*- c++ -*- */
+/*
+ * Copyright 2002 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.
+ */
+
+#ifndef _CONVOLUTIONAL_INTERLEAVER_H_
+#define _CONVOLUTIONAL_INTERLEAVER_H_
+
+#include <vector>
+#include <atsc/interleaver_fifo.h>
+#include <assert.h>
+
+/*!
+ * \brief template class for generic convolutional interleaver
+ */
+
+template<class symbol_type>
+class convolutional_interleaver {
+ public:
+
+ convolutional_interleaver (bool interleave_p, int nbanks, int fifo_size_incr);
+ virtual ~convolutional_interleaver ();
+
+ //! reset interleaver (flushes contents and resets commutator)
+ void reset ();
+
+ //! sync interleaver (resets commutator, but doesn't flush fifos)
+ void sync () { m_commutator = 0; }
+
+ //! return end to end delay in symbols (delay through concatenated interleaver / deinterleaver)
+ int end_to_end_delay ();
+
+ //! transform a single symbol
+ symbol_type transform (symbol_type input){
+ symbol_type retval = m_fifo[m_commutator]->stuff (input);
+ m_commutator++;
+ if (m_commutator >= m_nbanks)
+ m_commutator = 0;
+ return retval;
+ }
+
+ //! transform a bunch of symbols
+ void transform (symbol_type *out, const symbol_type *in, int nsymbols);
+
+protected:
+ int m_commutator;
+ int m_nbanks;
+ int m_fifo_size_incr;
+ std::vector<interleaver_fifo<symbol_type> *> m_fifo;
+};
+
+template<class symbol_type>
+convolutional_interleaver<symbol_type>::convolutional_interleaver (
+ bool interleave_p,
+ int nbanks,
+ int fifo_size_incr)
+{
+ assert (nbanks >= 1);
+ assert (fifo_size_incr >= 1);
+
+ m_nbanks = nbanks;
+ m_fifo_size_incr = fifo_size_incr;
+
+ m_fifo.resize (nbanks);
+
+ if (interleave_p){ // configure as interleaver
+ for (int i = 0; i < nbanks; i++)
+ m_fifo[i] = new interleaver_fifo<symbol_type>(i * fifo_size_incr);
+ }
+ else { // configure as de-interleaver
+ for (int i = 0; i < nbanks; i++)
+ m_fifo[nbanks - 1 - i] = new interleaver_fifo<symbol_type>(i * fifo_size_incr);
+ }
+ sync ();
+}
+
+template<class symbol_type>
+convolutional_interleaver<symbol_type>::~convolutional_interleaver ()
+{
+ for (int i = 0; i < m_nbanks; i++)
+ delete m_fifo[i];
+}
+
+template<class symbol_type> void
+convolutional_interleaver<symbol_type>::reset ()
+{
+ sync ();
+ for (int i = 0; i < m_nbanks; i++)
+ m_fifo[i]->reset ();
+}
+
+template<class symbol_type> int
+convolutional_interleaver<symbol_type>::end_to_end_delay ()
+{
+ int m = m_nbanks * m_fifo_size_incr;
+ return m * (m_nbanks - 1);
+}
+
+template<class symbol_type> void
+convolutional_interleaver<symbol_type>::transform (symbol_type *out,
+ const symbol_type *in,
+ int nsymbols)
+{
+ // we may want to unroll this a couple of times...
+ for (int i = 0; i < nsymbols; i++)
+ out[i] = transform (in[i]);
+}
+
+#endif /* _CONVOLUTIONAL_INTERLEAVER_H_ */