From a52f9a19581901beabc9111917965b9817231014 Mon Sep 17 00:00:00 2001
From: jcorgan
Date: Tue, 15 Apr 2008 21:31:29 +0000
Subject: Merged r8195:8205 from jcorgan/ecc into trunk.  Adds convolutional
 encoder and decoder corresponding to the R=1/2, K=7 CCSDS standard
 ("Voyager").

This code is a GNU Radio wrapper around a 1995-era KA9Q portable-C 
implementation, and is designed for continuous streaming data, not packets.

The encoder takes MSB packed bytes and outputs channel symbols 0 or 1.

The decoder uses soft-decision Viterbi decoding on a floating point stream of
(possibly noise corrupted) [1.0, 1.0] symbols, and outputs MSB packed
decoded bytes.

Benchmarking on a 2.16 GHz Intel Core 2 Duo shows 4.7 Mbps decoding rate at 
100% CPU usage (single core).  (There is a newer KA9Q library that implements 
SIMD speed ups with correspondingly faster performance.)

The KA9Q library is placed into src/lib/viterbi.  It could use some cleanup,
file/function renaming, and refactoring, or even replacement with the newer
libfec code that is available.



git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@8206 221aa14e-8319-0410-a670-987f0aec2ac5
---
 gnuradio-core/src/lib/viterbi/encode.cc | 54 +++++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 gnuradio-core/src/lib/viterbi/encode.cc

(limited to 'gnuradio-core/src/lib/viterbi/encode.cc')

diff --git a/gnuradio-core/src/lib/viterbi/encode.cc b/gnuradio-core/src/lib/viterbi/encode.cc
new file mode 100644
index 000000000..01acb3987
--- /dev/null
+++ b/gnuradio-core/src/lib/viterbi/encode.cc
@@ -0,0 +1,54 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2008 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.
+ */
+
+/*
+ * This is a minimal example demonstrating how to call the ECC encoder
+ * in continuous streaming mode.  It accepts data on stdin and writes to 
+ * stdout.
+ * 
+ * FIXME: This does not flush the final bits out of the encoder.
+ *
+ */
+
+extern "C" {
+#include "viterbi.h"
+}
+
+#include <cstdio>
+
+#define MAXCHUNKSIZE 4096
+#define MAXENCSIZE MAXCHUNKSIZE*16
+
+int main()
+{
+  unsigned char encoder_state = 0;
+  unsigned char data[MAXCHUNKSIZE];
+  unsigned char syms[MAXENCSIZE];
+  
+  while (!feof(stdin)) {
+    unsigned int n = fread(data, 1, MAXCHUNKSIZE, stdin);
+    encoder_state = encode(syms, data, n, encoder_state);
+    fwrite(syms, 1, n*16, stdout);
+  }
+
+  return 0;
+}
-- 
cgit 


From f919f9dcbb54a08e6e26d6c229ce92fb784fa1b2 Mon Sep 17 00:00:00 2001
From: Tom Rondeau
Date: Fri, 13 Apr 2012 18:36:53 -0400
Subject: Removed whitespace and added dtools/bin/remove-whitespace as a tool
 to do this in the future.

The sed script was provided by Moritz Fischer.
---
 gnuradio-core/src/lib/viterbi/encode.cc | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

(limited to 'gnuradio-core/src/lib/viterbi/encode.cc')

diff --git a/gnuradio-core/src/lib/viterbi/encode.cc b/gnuradio-core/src/lib/viterbi/encode.cc
index 01acb3987..83a85fcac 100644
--- a/gnuradio-core/src/lib/viterbi/encode.cc
+++ b/gnuradio-core/src/lib/viterbi/encode.cc
@@ -1,19 +1,19 @@
 /* -*- c++ -*- */
 /*
  * Copyright 2008 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,
@@ -22,9 +22,9 @@
 
 /*
  * This is a minimal example demonstrating how to call the ECC encoder
- * in continuous streaming mode.  It accepts data on stdin and writes to 
+ * in continuous streaming mode.  It accepts data on stdin and writes to
  * stdout.
- * 
+ *
  * FIXME: This does not flush the final bits out of the encoder.
  *
  */
@@ -43,7 +43,7 @@ int main()
   unsigned char encoder_state = 0;
   unsigned char data[MAXCHUNKSIZE];
   unsigned char syms[MAXENCSIZE];
-  
+
   while (!feof(stdin)) {
     unsigned int n = fread(data, 1, MAXCHUNKSIZE, stdin);
     encoder_state = encode(syms, data, n, encoder_state);
-- 
cgit