aboutsummaryrefslogtreecommitdiffstats
path: root/src/FrequencyInterleaver.cpp
blob: 886a03c0bdd25100bbe1cd4ca35fd54d208e1bb2 (plain)
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
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/*
   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty
   the Queen in Right of Canada (Communications Research Center Canada)
 */
/*
   This file is part of ODR-DabMod.

   ODR-DabMod 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 of the
   License, or (at your option) any later version.

   ODR-DabMod 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 ODR-DabMod.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "FrequencyInterleaver.h"
#include "PcDebug.h"

#include <stdio.h>
#include <stdexcept>
#include <malloc.h>
#include <complex>

typedef std::complex<float> complexf;


FrequencyInterleaver::FrequencyInterleaver(size_t mode) :
    ModCodec(ModFormat(0), ModFormat(0))
{
    PDEBUG("FrequencyInterleaver::FrequencyInterleaver(%zu) @ %p\n",
            mode, this);

    size_t num;
    size_t alpha = 13;
    size_t beta;
    switch (mode) {
    case 1:
        d_carriers = 1536;
        num = 2048;
        beta = 511;
        break;
    case 2:
        d_carriers = 384;
        num = 512;
        beta = 127;
        break;
    case 3:
        d_carriers = 192;
        num = 256;
        beta = 63;
        break;
    case 0:
    case 4:
        d_carriers = 768;
        num = 1024;
        beta = 255;
        break;
    default:
        PDEBUG("Carriers: %zu\n", (d_carriers >> 1) << 1);
        throw std::runtime_error("FrequencyInterleaver::FrequencyInterleaver "
                "nb of carriers invalid!");
        break;
    }

    d_indexes = (size_t*)memalign(16, d_carriers * sizeof(size_t));
    size_t* index = d_indexes;
    size_t perm = 0;
    PDEBUG("i: %4u, R: %4u\n", 0, 0);
    for (size_t j = 1; j < num; ++j) {
        perm = (alpha * perm + beta) & (num - 1);
        if (perm >= ((num - d_carriers) / 2)
                && perm <= (num - (num - d_carriers) / 2)
                && perm != (num / 2)) {
            PDEBUG("i: %4zu, R: %4zu, d: %4zu, n: %4zu, k: %5zi, index: %zu\n",
                    j, perm, perm, index - d_indexes, perm - num / 2,
                    perm > num / 2
                    ?  perm - (1 + (num / 2))
                    : perm + (d_carriers - (num / 2)));
            *(index++) = perm > num / 2 ?
                perm - (1 + (num / 2)) : perm + (d_carriers - (num / 2));
        } else {
            PDEBUG("i: %4zu, R: %4zu\n", j, perm);
        }
    }
}


FrequencyInterleaver::~FrequencyInterleaver()
{
    PDEBUG("FrequencyInterleaver::~FrequencyInterleaver() @ %p\n", this);

    free(d_indexes);
}


int FrequencyInterleaver::process(Buffer* const dataIn, Buffer* dataOut)
{
    PDEBUG("FrequencyInterleaver::process"
            "(dataIn: %p, sizeIn: %zu, dataOut: %p, sizeOut: %zu)\n",
            dataIn, dataIn->getLength(), dataOut, dataOut->getLength());

    dataOut->setLength(dataIn->getLength());

    const complexf* in = reinterpret_cast<const complexf*>(dataIn->getData());
    complexf* out = reinterpret_cast<complexf*>(dataOut->getData());
    size_t sizeIn = dataIn->getLength() / sizeof(complexf);

    if (sizeIn % d_carriers != 0) {
        throw std::runtime_error(
                "FrequencyInterleaver::process input size not valid!");
    }

    for (size_t i = 0; i < sizeIn;) {
//        memset(out, 0, d_carriers * sizeof(complexf));
        for (size_t j = 0; j < d_carriers; i += 4, j += 4) {
            out[d_indexes[j]] = in[i];
            out[d_indexes[j + 1]] = in[i + 1];
            out[d_indexes[j + 2]] = in[i + 2];
            out[d_indexes[j + 3]] = in[i + 3];
        }
        out += d_carriers;
    }

    return 1;
}