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
|
/* -*- c++ -*- */
/*
* Copyright 2015,2016 Free Software Foundation, Inc.
*
* SPDX-License-Identifier: GPL-3.0-or-later
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "dvbt_reed_solomon_enc_impl.h"
#include <gnuradio/io_signature.h>
namespace gr {
namespace dtv {
static const int rs_init_symsize = 8;
static const int rs_init_fcr = 0; // first consecutive root
static const int rs_init_prim = 1; // primitive is 1 (alpha)
dvbt_reed_solomon_enc::sptr dvbt_reed_solomon_enc::make(
int p, int m, int gfpoly, int n, int k, int t, int s, int blocks)
{
return gnuradio::make_block_sptr<dvbt_reed_solomon_enc_impl>(
p, m, gfpoly, n, k, t, s, blocks);
}
/*
* The private constructor
*/
dvbt_reed_solomon_enc_impl::dvbt_reed_solomon_enc_impl(
int p, int m, int gfpoly, int n, int k, int t, int s, int blocks)
: block("dvbt_reed_solomon",
io_signature::make(1, 1, sizeof(unsigned char) * blocks * (k - s)),
io_signature::make(1, 1, sizeof(unsigned char) * blocks * (n - s))),
d_n(n),
d_k(k),
d_s(s),
d_blocks(blocks)
{
d_rs = init_rs_char(rs_init_symsize, gfpoly, rs_init_fcr, rs_init_prim, (n - k));
if (d_rs == NULL) {
GR_LOG_FATAL(d_logger, "Reed-Solomon Encoder, cannot allocate memory for d_rs.");
throw std::bad_alloc();
}
// The full input frame size (d_k) (no need to add in d_s, as the block input is the
// pre-shortedned K)
d_data = (unsigned char*)malloc(sizeof(unsigned char) * (d_k));
if (d_data == NULL) {
GR_LOG_FATAL(d_logger,
"Reed-Solomon Encoder, cannot allocate memory for d_data.");
free_rs_char(d_rs);
throw std::bad_alloc();
}
}
/*
* Our virtual destructor.
*/
dvbt_reed_solomon_enc_impl::~dvbt_reed_solomon_enc_impl()
{
free(d_data);
free_rs_char(d_rs);
}
void dvbt_reed_solomon_enc_impl::forecast(int noutput_items,
gr_vector_int& ninput_items_required)
{
ninput_items_required[0] = noutput_items;
}
void dvbt_reed_solomon_enc_impl::encode(const unsigned char* in, unsigned char* out)
{
// Shortened Reed-Solomon: prepend zero bytes to message (discarded after encoding)
std::memset(d_data, 0, d_s);
// This is the number of data bytes we need from the input stream.
int shortened_k = d_k - d_s;
std::memcpy(&d_data[d_s], in, shortened_k);
// Copy input message to output then append Reed-Solomon bits
std::memcpy(out, in, shortened_k);
encode_rs_char(d_rs, d_data, &out[shortened_k]);
}
int dvbt_reed_solomon_enc_impl::general_work(int noutput_items,
gr_vector_int& ninput_items,
gr_vector_const_void_star& input_items,
gr_vector_void_star& output_items)
{
const unsigned char* in = (const unsigned char*)input_items[0];
unsigned char* out = (unsigned char*)output_items[0];
int j = 0;
int k = 0;
for (int i = 0; i < noutput_items * d_blocks; i++) {
encode(in + j, out + k);
j += (d_k - d_s);
k += (d_n - d_s);
}
// Tell runtime system how many input items we consumed on
// each input stream.
consume_each(noutput_items);
// Tell runtime system how many output items we produced.
return noutput_items;
}
} /* namespace dtv */
} /* namespace gr */
|
