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Diffstat (limited to 'lib/ReedSolomon.cpp')
| -rw-r--r-- | lib/ReedSolomon.cpp | 118 | 
1 files changed, 118 insertions, 0 deletions
| diff --git a/lib/ReedSolomon.cpp b/lib/ReedSolomon.cpp new file mode 100644 index 0000000..1bf0b24 --- /dev/null +++ b/lib/ReedSolomon.cpp @@ -0,0 +1,118 @@ +/* +   Copyright (C) 2005, 2006, 2007, 2008, 2009 Her Majesty the Queen in Right +   of Canada (Communications Research Center Canada) + +   Copyright (C) 2016 +   Matthias P. Braendli, matthias.braendli@mpb.li + +    http://www.opendigitalradio.org +   */ +/* +   This file is part of ODR-DabMux. + +   ODR-DabMux 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-DabMux 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-DabMux.  If not, see <http://www.gnu.org/licenses/>. +   */ + +#include "ReedSolomon.h" +#include <vector> +#include <algorithm> +#include <stdexcept> +#include <sstream> +#include <stdio.h>          // For galois.h ... +#include <string.h>         // For memcpy + +extern "C" { +#include "fec/fec.h" +} +#include <assert.h> + +#define SYMSIZE     8 + + +ReedSolomon::ReedSolomon(int N, int K, bool reverse, int gfpoly, int firstRoot, int primElem) +{ +    setReverse(reverse); + +    m_N = N; +    m_K = K; + +    const int symsize = SYMSIZE; +    const int nroots = N - K; // For EDI PFT, this must be 48 +    const int pad = ((1 << symsize) - 1) - N; // is 255-N + +    rsData = init_rs_char(symsize, gfpoly, firstRoot, primElem, nroots, pad); + +    if (rsData == nullptr) { +        std::stringstream ss; +        ss << "Invalid Reed-Solomon parameters! " << +            "N=" << N << " ; K=" << K << " ; pad=" << pad; +        throw std::invalid_argument(ss.str()); +    } +} + + +ReedSolomon::~ReedSolomon() +{ +    if (rsData != nullptr) { +        free_rs_char(rsData); +    } +} + + +void ReedSolomon::setReverse(bool state) +{ +    reverse = state; +} + + +int ReedSolomon::encode(void* data, void* fec, size_t size) +{ +    uint8_t* input = reinterpret_cast<uint8_t*>(data); +    uint8_t* output = reinterpret_cast<uint8_t*>(fec); +    int ret = 0; + +    if (reverse) { +        std::vector<uint8_t> buffer(m_N); + +        memcpy(&buffer[0], input, m_K); +        memcpy(&buffer[m_K], output, m_N - m_K); + +        ret = decode_rs_char(rsData, &buffer[0], nullptr, 0); +        if ((ret != 0) && (ret != -1)) { +            memcpy(input, &buffer[0], m_K); +            memcpy(output, &buffer[m_K], m_N - m_K); +        } +    } +    else { +        encode_rs_char(rsData, input, output); +    } + +    return ret; +} + + +int ReedSolomon::encode(void* data, size_t size) +{ +    uint8_t* input = reinterpret_cast<uint8_t*>(data); +    int ret = 0; + +    if (reverse) { +        ret = decode_rs_char(rsData, input, nullptr, 0); +    } +    else { +        encode_rs_char(rsData, input, &input[m_K]); +    } + +    return ret; +} | 
