README change

1 files changed, 53 insertions, 0 deletions

diff --git a/gnuradio-core/src/lib/viterbi/viterbi.h b/gnuradio-core/src/lib/viterbi/viterbi.h
new file mode 100644
index 000000000..bcdbe116d
--- /dev/null
+++ b/gnuradio-core/src/lib/viterbi/viterbi.h
@@ -0,0 +1,53 @@
+/*
+ * 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.
+ */
+
+/* The path memory for each state is 32 bits. This is slightly shorter
+ * than we'd like for K=7, especially since we chain back every 8 bits.
+ * But it fits so nicely into a 32-bit machine word...
+ */
+
+#include <gr_core_api.h>
+
+struct viterbi_state {
+  unsigned long path;	/* Decoded path to this state */
+  long metric;		/* Cumulative metric to this state */
+};
+
+GR_CORE_API
+int gen_met(int mettab[2][256],	/* Metric table */
+	    int amp,		/* Signal amplitude */
+	    double esn0,	/* Es/N0 ratio in dB */
+	    double bias, 	/* Metric bias */
+	    int scale);		/* Scale factor */
+
+GR_CORE_API unsigned char
+encode(unsigned char *symbols, unsigned char *data,
+       unsigned int nbytes,unsigned char encstate);
+
+GR_CORE_API void
+viterbi_chunks_init(struct viterbi_state* state);
+
+ GR_CORE_API void
+viterbi_butterfly2(unsigned char *symbols, int mettab[2][256],
+		   struct viterbi_state *state0, struct viterbi_state *state1);
+
+GR_CORE_API unsigned char
+viterbi_get_output(struct viterbi_state *state, unsigned char *outbuf);