1 files changed, 129 insertions, 0 deletions
diff --git a/gr-dtv/lib/atsc_rs_decoder_impl.cc b/gr-dtv/lib/atsc_rs_decoder_impl.cc
new file mode 100644
index 0000000000..890afdef3d
--- /dev/null
+++ b/gr-dtv/lib/atsc_rs_decoder_impl.cc
@@ -0,0 +1,129 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2014 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 "atsc_rs_decoder_impl.h"
+#include "gnuradio/dtv/atsc_consts.h"
+#include <gnuradio/io_signature.h>
+
+namespace gr {
+  namespace dtv {
+
+    static const int rs_init_symsize =     8;
+    static const int rs_init_gfpoly  = 0x11d;
+    static const int rs_init_fcr     =     0;	// first consecutive root
+    static const int rs_init_prim    =     1;	// primitive is 1 (alpha)
+    static const int rs_init_nroots  =    20;
+
+    static const int N = (1 << rs_init_symsize) - 1;	// 255
+    static const int K = N - rs_init_nroots;		// 235
+
+    static const int amount_of_pad = N - ATSC_MPEG_RS_ENCODED_LENGTH;	  // 48
+
+    atsc_rs_decoder::sptr
+    atsc_rs_decoder::make()
+    {
+      return gnuradio::get_initial_sptr
+	(new atsc_rs_decoder_impl());
+    }
+
+    atsc_rs_decoder_impl::atsc_rs_decoder_impl()
+      : gr::sync_block("dtv_atsc_rs_decoder",
+                  io_signature::make(1, 1, sizeof(atsc_mpeg_packet_rs_encoded)),
+                  io_signature::make(1, 1, sizeof(atsc_mpeg_packet_no_sync)))
+    {
+      d_rs = init_rs_char (rs_init_symsize, rs_init_gfpoly, rs_init_fcr, rs_init_prim, rs_init_nroots);
+      assert (d_rs != 0);
+      nerrors_corrrected_count = 0;
+      bad_packet_count = 0;
+      total_packets = 0;
+      reset_counter = 0;
+      reset();
+    }
+
+    int atsc_rs_decoder_impl::decode (atsc_mpeg_packet_no_sync &out, const atsc_mpeg_packet_rs_encoded &in)
+    {
+      unsigned char tmp[N];
+      int ncorrections;
+
+      assert ((int)(amount_of_pad + sizeof (in.data)) == N);
+
+      // add missing prefix zero padding to message
+      memset (tmp, 0, amount_of_pad);
+      memcpy (&tmp[amount_of_pad], in.data, sizeof (in.data));
+
+      // correct message...
+      ncorrections = decode_rs_char (d_rs, tmp, 0, 0);
+
+      // copy corrected message to output, skipping prefix zero padding
+      memcpy (out.data, &tmp[amount_of_pad], sizeof (out.data));
+
+      return ncorrections;
+    }
+
+    atsc_rs_decoder_impl::~atsc_rs_decoder_impl()
+    {
+      if (d_rs)
+        free_rs_char (d_rs);
+      d_rs = 0;
+    }
+
+    int
+    atsc_rs_decoder_impl::work (int noutput_items,
+                        gr_vector_const_void_star &input_items,
+                        gr_vector_void_star &output_items)
+    {
+      const atsc_mpeg_packet_rs_encoded *in = (const atsc_mpeg_packet_rs_encoded *) input_items[0];
+      atsc_mpeg_packet_no_sync *out = (atsc_mpeg_packet_no_sync *) output_items[0];
+
+      for (int i = 0; i < noutput_items; i++){
+        assert(in[i].pli.regular_seg_p());
+        out[i].pli = in[i].pli;			// copy pipeline info...
+
+        int nerrors_corrrected = decode(out[i], in[i]);
+        out[i].pli.set_transport_error(nerrors_corrrected == -1);
+        if( nerrors_corrrected == -1 )
+          bad_packet_count++;
+        else
+          nerrors_corrrected_count += nerrors_corrrected;
+      }
+
+      total_packets += noutput_items;
+      reset_counter++;
+
+      if( reset_counter > 100 )
+      {
+        std::cout << "Error rate: " << (float)nerrors_corrrected_count/total_packets << "\tPacket error rate: " << (float)bad_packet_count/total_packets << std::endl;
+        nerrors_corrrected_count = 0;
+        bad_packet_count = 0;
+        total_packets = 0;
+        reset_counter = 0;
+      }
+
+      return noutput_items;
+    }
+
+  } /* namespace dtv */
+} /* namespace gr */