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authorMatthias P. Braendli <matthias.braendli@mpb.li>2019-06-07 10:14:51 +0200
committerMatthias P. Braendli <matthias.braendli@mpb.li>2019-06-07 10:14:51 +0200
commit8b0d4b647a3ac2e21e6a8e7a902eea3ae462e213 (patch)
treec0296c305409bb7fc373625aea05c2f57054eb5c /lib/ReedSolomon.cpp
parent43f4a3a2a695c303bd4fdfbd7fec6def29284f2e (diff)
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Work on STI-D/EDI input
Diffstat (limited to 'lib/ReedSolomon.cpp')
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diff --git a/lib/ReedSolomon.cpp b/lib/ReedSolomon.cpp
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+/*
+ 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()
+{
+ 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;
+}