1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
/* -*- 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 <stdlib.h>
#include <stdio.h>
#include <atsci_reed_solomon.h>
#include <qa_atsci_reed_solomon.h>
#include <string.h>
static const int NROOTS = 20;
static const int NTRIALS = 100;
static const int NN = ATSC_MPEG_RS_ENCODED_LENGTH;
void
qa_atsci_reed_solomon::t0_reed_solomon ()
{
atsc_mpeg_packet_no_sync in;
atsc_mpeg_packet_rs_encoded enc;
atsc_mpeg_packet_no_sync out;
int derrors;
int errlocs[NN];
int errval;
int errloc;
int decoder_errors = 0;
for (int nt = 0; nt < NTRIALS; nt++){
// test up to the error correction capacity of the code
for (int errors = 0; errors <= NROOTS*2; errors++){
// load block with random data and encode
for (int i = 0; i < ATSC_MPEG_DATA_LENGTH; i++)
in.data[i] = random () & 0xff;
rs.encode (enc, in);
memset (errlocs, 0, sizeof (errlocs));
for (int i = 0; i < errors; i++){
do {
errval = random () & 0xff;
} while (errval == 0); // error value must be non-zero
do {
errloc = random () % NN;
} while (errlocs[errloc] != 0); // must not choose the same location twice
errlocs[errloc] = 1;
enc.data[errloc] ^= errval; // cause the error
}
// decode the errored block
derrors = rs.decode (out, enc);
if (errors <= NROOTS/2) {
// We should have handled all these errors and corrected them.
if (derrors != errors){
fprintf (stderr, " decoder says %d errors, true number is %d\n", derrors, errors);
decoder_errors++;
}
if (in != out){
fprintf (stderr, " uncorrected errors!\n");
decoder_errors++;
}
} else {
// We have been given more errors than we could cope with. Make
// sure that we detect these errors. Complain if we get incorrect
// block but don't say it's incorrect.
bool differs = (in != out);
if (differs && (derrors < 0)) {
// Reported uncorrectable error accurately
} else if (differs) {
fprintf (stderr,
" decoder found %d of %d errors, but incorrect block\n",
derrors, errors);
} else {
fprintf (stderr, " decoder corrected %d of %d errors unexpectedly\n",
derrors, errors);
}
}
}
}
CPPUNIT_ASSERT (decoder_errors == 0);
}
|
