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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.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <cppunit/TestAssert.h>
#include <stdio.h>
#include <atsci_fake_single_viterbi.h>
#include <qa_atsci_fake_single_viterbi.h>
#include <random.h>
#include <string.h>
static const int NTRIALS = 50;
static const int MAXERRORS = 10;
static const int NN = 200;
static const int MAXDIBIT = 3;
void
qa_atsci_fake_single_viterbi::encode_block (unsigned char *out, unsigned char *in,
unsigned int n)
{
for (unsigned int i = 0; i < n; i++) {
out[i] = encoder.encode(in[i]);
}
}
void
qa_atsci_fake_single_viterbi::decode_block (unsigned char *out, unsigned char *in,
unsigned int n)
{
for (unsigned int i = 0; i < n; i++) {
out[i] = decoder.decode ((2*in[i]-7) + noise ());
}
}
float
qa_atsci_fake_single_viterbi::noise ()
{
#if 1
return 2.0 * ((float) random () / RANDOM_MAX - 0.5);;
#else
return 0;
#endif
}
void
qa_atsci_fake_single_viterbi::t0 ()
{
static const int blocklen = NN;
unsigned char in[blocklen];
unsigned char enc[blocklen];
unsigned char out[blocklen];
int decoder_errors = 0;
int delay = decoder.delay ();
int i;
// printf (" Delay is %d.\n", delay);
srandom (27); // reproducable sequence of "random" values
for (int nt = 0; nt < NTRIALS; nt++){
// load block with random data and encode
for (i = 0; i < (blocklen-delay); i++)
in[i] = random () & MAXDIBIT;
for ( ; i < blocklen; i++)
in[i] = 0; /* To empty the delay buffers */
encoder.reset ();
encode_block (enc, in, blocklen);
decoder.reset ();
// decode the block
decode_block (out, enc, blocklen);
// int offset = delay/4;
int offset = 2;
bool differs = (memcmp (in+offset,
out+delay+offset, blocklen-(delay+offset)));
// initial values after reset are 0
for (i = 0; i < delay; i++){
if (out[i] != 0)
printf (" initial output at %i is %X, not 0\n",
i, out[i]);
}
if (differs){
printf (" incorrect data, trial #%d\n", nt);
printf ("\n Erroneous result dibits:");
for (int erri = 0; erri < (NN-delay); erri++) {
if (in[erri] != out[erri+delay])
printf (" %d", erri);
}
printf ("\n In: ");
for (int erri = 0; erri < (NN-delay); erri++) {
printf (" %d", in[erri]);
}
printf ("\n Out: ");
for (int erri = 0; erri < (NN-delay); erri++) {
printf (" %d", out[erri+delay]);
}
printf ("\n Errs:");
for (int erri = 0; erri < (NN-delay); erri++) {
printf (" %c", (in[erri] != out[erri+delay])? '*': ' ');
}
printf ("\n THIS IS A REAL PROBLEM.\n");
decoder_errors++;
}
}
printf (" Summary: %d decoder errors out of %d trials.\n",
decoder_errors, NTRIALS);
CPPUNIT_ASSERT (decoder_errors == 0);
}
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