1 files changed, 204 insertions, 0 deletions
diff --git a/gr-fec/lib/cc_encoder_impl.cc b/gr-fec/lib/cc_encoder_impl.cc
new file mode 100644
index 0000000000..75d7dcd66b
--- /dev/null
+++ b/gr-fec/lib/cc_encoder_impl.cc
@@ -0,0 +1,204 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013-2014 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 "cc_encoder_impl.h"
+#include <math.h>
+#include <boost/assign/list_of.hpp>
+#include <volk/volk_typedefs.h>
+#include <volk/volk.h>
+#include <sstream>
+#include <stdio.h>
+#include <vector>
+#include <gnuradio/fec/generic_encoder.h>
+#include <gnuradio/fec/cc_common.h>
+
+namespace gr {
+  namespace fec {
+    namespace code {
+
+      generic_encoder::sptr
+      cc_encoder::make(int frame_size, int k, int rate,
+                       std::vector<int> polys, int start_state,
+                       cc_mode_t mode, bool padded)
+      {
+        return generic_encoder::sptr
+          (new cc_encoder_impl(frame_size, k, rate,
+                               polys, start_state,
+                               mode, padded));
+      }
+
+      cc_encoder_impl::cc_encoder_impl(int frame_size, int k, int rate,
+                                       std::vector<int> polys, int start_state,
+                                       cc_mode_t mode, bool padded)
+        : generic_encoder("cc_encoder"),
+          d_rate(rate), d_k(k), d_polys(polys),
+          d_start_state(start_state),
+          d_mode(mode), d_padding(0)
+      {
+        if(static_cast<size_t>(d_rate) != d_polys.size()) {
+          throw std::runtime_error("cc_encoder: Number of polynomials must be the same as the value of rate");
+        }
+
+        partab_init();
+
+        // set up a padding factor. If padding, extends the encoding
+        // by this many bits to fit into a full byte.
+        if(padded && (mode == CC_TERMINATED)) {
+          d_padding = static_cast<int>(8.0f*ceilf(d_rate*(d_k-1)/8.0f) - (d_rate*(d_k-1)));
+        }
+
+        d_max_frame_size = frame_size;
+        set_frame_size(frame_size);
+      }
+
+      cc_encoder_impl::~cc_encoder_impl()
+      {
+      }
+
+      int
+      cc_encoder_impl::get_output_size()
+      {
+        return d_output_size;
+      }
+
+      int
+      cc_encoder_impl::get_input_size()
+      {
+        return d_frame_size;
+      }
+
+      bool
+      cc_encoder_impl::set_frame_size(unsigned int frame_size)
+      {
+        bool ret = true;
+        if(frame_size > d_max_frame_size) {
+          GR_LOG_INFO(d_logger, boost::format("tried to set frame to %1%; max possible is %2%") \
+                      % frame_size % d_max_frame_size);
+          frame_size = d_max_frame_size;
+          ret = false;
+        }
+
+        d_frame_size = frame_size;
+
+        if(d_mode == CC_TERMINATED) {
+          d_output_size = d_rate * (d_frame_size + d_k - 1) + d_padding;
+        }
+        /*
+        else if(d_trunc_intrinsic) {
+          int cnt = 0;
+          for(int i = 0; i < d_rate; ++i) {
+            if (d_polys[i] != 1) {
+              cnt++;
+            }
+          }
+          d_output_size = (d_rate * (d_frame_size)) + (cnt * (d_k - 1));
+        }
+        */
+        else {
+          d_output_size = d_rate * d_frame_size;
+        }
+
+        return ret;
+      }
+
+      double
+      cc_encoder_impl::rate()
+      {
+        return static_cast<double>(d_rate);
+      }
+
+      int
+      cc_encoder_impl::parity(int x)
+      {
+        x ^= (x >> 16);
+        x ^= (x >> 8);
+        return parityb(x);
+      }
+
+      int
+      cc_encoder_impl::parityb(unsigned char x)
+      {
+        return Partab[x];
+      }
+
+      void
+      cc_encoder_impl::partab_init(void)
+      {
+        int i,cnt,ti;
+
+        /* Initialize parity lookup table */
+        for(i=0;i<256;i++){
+          cnt = 0;
+          ti = i;
+          while(ti){
+            if(ti & 1)
+              cnt++;
+            ti >>= 1;
+          }
+          Partab[i] = cnt & 1;
+        }
+      }
+
+      void
+      cc_encoder_impl::generic_work(void *in_buffer, void *out_buffer)
+      {
+        const unsigned char *in = (const unsigned char *) in_buffer;
+        unsigned char *out = (unsigned char *) out_buffer;
+
+        unsigned char my_state = d_start_state;
+
+        if(d_mode == CC_TAILBITING) {
+          for(unsigned int i = 0; i < d_k - 1; ++i) {
+            my_state = (my_state << 1) | (in[d_frame_size - (d_k - 1)  + i] & 1);
+          }
+        }
+
+        for(unsigned int i = 0; i < d_frame_size; ++i) {
+          my_state = (my_state << 1) | (in[i] & 1);
+          for(unsigned int j = 0; j < d_rate; ++j) {
+            out[i * d_rate + j] = parity(my_state & d_polys[j]) == 0 ? 0 : 1;
+          }
+        }
+
+        if(d_mode == CC_TERMINATED) {
+          for(unsigned int i = 0; i < d_k - 1; ++i) {
+            my_state = (my_state << 1) | ((d_start_state >> (d_k - 2 - i)) & 1);
+            for(unsigned int j = 0; j < d_rate; ++j) {
+              out[(i + d_frame_size) * d_rate + j] = parity(my_state & d_polys[j]) == 0 ? 0 : 1;
+            }
+          }
+        }
+
+        if(d_mode == CC_TRUNCATED) {
+          my_state = d_start_state;
+        }
+
+        d_start_state = my_state;
+      }
+
+    } /* namespace code */
+  } /* namespace fec */
+} /* namespace gr */