diff options
| -rw-r--r-- | src/DabMux.cpp | 13 | ||||
| -rw-r--r-- | src/Makefile.am | 1 | ||||
| -rw-r--r-- | src/dabOutput/edi/PFT.cpp | 91 | ||||
| -rw-r--r-- | src/dabOutput/edi/PFT.h | 77 |
4 files changed, 179 insertions, 3 deletions
diff --git a/src/DabMux.cpp b/src/DabMux.cpp index 3859734..6003c48 100644 --- a/src/DabMux.cpp +++ b/src/DabMux.cpp @@ -116,6 +116,7 @@ typedef DWORD32 uint32_t; #include "dabOutput/edi/TagItems.h" #include "dabOutput/edi/TagPacket.h" #include "dabOutput/edi/AFPacket.h" +#include "dabOutput/edi/PFT.h" #include "crc.h" #include "UdpSocket.h" #include "InetAddress.h" @@ -673,7 +674,10 @@ int main(int argc, char *argv[]) TagPacket edi_tagpacket; // The TagPacket will then be placed into an AFPacket - AFPacketiser edi_afPacket(EDI_AFPACKET_PROTOCOLTYPE_TAGITEMS); + AFPacketiser edi_afPacketiser(EDI_AFPACKET_PROTOCOLTYPE_TAGITEMS); + + // The AF Packet will be protected with reed-solomon and split in fragments + PFT edi_pft(128, 3); edi_tagDETI.atstf = 0; // TODO add ATST support @@ -1954,11 +1958,14 @@ int main(int argc, char *argv[]) edi_tagpacket.tag_items.push_back(&(*tag)); } - vector<uint8_t> edi_afpacketData = edi_afPacket.Assemble(edi_tagpacket); + AFPacket edi_afpacket = edi_afPacketiser.Assemble(edi_tagpacket); + + vector< vector<uint8_t> > edi_fragments = edi_pft.ProtectAndFragment(edi_afpacket); #if EDI_DEBUG std::ostream_iterator<uint8_t> debug_iterator(edi_debug_file); - std::copy(edi_afpacketData.begin(), edi_afpacketData.end(), debug_iterator); + std::copy(edi_afpacket.begin(), edi_afpacket.end(), debug_iterator); + fprintf(stderr, "EDI number of fragments %zu\n", edi_fragments.size()); #endif #if _DEBUG diff --git a/src/Makefile.am b/src/Makefile.am index 709abe4..b65b9d2 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -73,6 +73,7 @@ odr_dabmux_SOURCES =DabMux.cpp DabMux.h \ dabOutput/edi/AFPacket.cpp dabOutput/edi/AFPacket.h \ dabOutput/edi/TagItems.cpp dabOutput/edi/TagItems.h \ dabOutput/edi/TagPacket.cpp dabOutput/edi/TagPacket.h \ + dabOutput/edi/PFT.cpp dabOutput/edi/PFT.h \ bridge.h bridge.c \ utils.cpp utils.h \ MuxElements.cpp MuxElements.h \ diff --git a/src/dabOutput/edi/PFT.cpp b/src/dabOutput/edi/PFT.cpp new file mode 100644 index 0000000..e14a008 --- /dev/null +++ b/src/dabOutput/edi/PFT.cpp @@ -0,0 +1,91 @@ +/* + Copyright (C) 2013 Matthias P. Braendli + http://mpb.li + + EDI output, + Protection, Fragmentation and Transport. (PFT) + + Are supported: + Reed-Solomon and Fragmentation + + This implements part of PFT as defined ETSI TS 102 821. + + */ +/* + This file is part of CRC-DabMux. + + CRC-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. + + CRC-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 CRC-DabMux. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "config.h" +#include <vector> +#include <list> +#include <stdint.h> +#include "PFT.h" +#include "ReedSolomon.h" + +using namespace std; + +typedef vector<uint8_t> Chunk; + + +RSPacket PFT::Protect(AFPacket af_packet) +{ + RSPacket rs_packet; + + m_num_chunks = af_packet.size() / 207 + 1; + const size_t zero_pad = m_num_chunks * m_k - af_packet.size(); + + // add zero padding to last chunk + for (size_t i = 0; i < zero_pad; i++) { + af_packet.push_back(0); + } + + for (size_t i = 1; i < af_packet.size(); i+= m_k) { + // add new chunk to the list + Chunk c(m_k + ParityBytes); + + for (size_t j = 0; j < m_k; j++) { + c[j] = af_packet[i+j]; + } + + // calculate RS for chunk + m_encoder.encode(&c.front(), c.size()); + + rs_packet.insert(rs_packet.end(), c.begin(), c.end()); + } + + return rs_packet; +} + +vector< vector<uint8_t> > PFT::ProtectAndFragment(AFPacket af_packet) +{ + RSPacket rs_packet = Protect(af_packet); + + const size_t max_payload_size = ( m_num_chunks * ParityBytes ) / (m_m + 1); + + const size_t fragment_size = m_num_chunks * (m_k + ParityBytes) / max_payload_size; + const size_t num_fragments = m_num_chunks * (m_k + ParityBytes) / fragment_size; + + vector< vector<uint8_t> > fragments(num_fragments); + + for (size_t i = 0; i < num_fragments; i++) { + for (size_t j = 0; j < fragment_size; j++) { + fragments[i][j] = rs_packet[j*num_fragments + i]; //TODO that's wrong. fix it. + } + } + + return fragments; +} + diff --git a/src/dabOutput/edi/PFT.h b/src/dabOutput/edi/PFT.h new file mode 100644 index 0000000..713170f --- /dev/null +++ b/src/dabOutput/edi/PFT.h @@ -0,0 +1,77 @@ +/* + Copyright (C) 2013 Matthias P. Braendli + http://mpb.li + + EDI output, + Protection, Fragmentation and Transport. (PFT) + + Are supported: + Reed-Solomon and Fragmentation + + This implements part of PFT as defined ETSI TS 102 821. + + */ +/* + This file is part of CRC-DabMux. + + CRC-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. + + CRC-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 CRC-DabMux. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef _PFT_H_ +#define _PFT_H_ + +#include "config.h" +#include <vector> +#include <list> +#include <stdint.h> +#include "AFPacket.h" +#include "Log.h" +#include "ReedSolomon.h" + +typedef std::vector<uint8_t> RSPacket; + +class PFT +{ + public: + static const int ParityBytes = 255 - 207; + + PFT(unsigned int RSDataWordLength, unsigned int NumRecoverableFragments) : + m_k(RSDataWordLength), m_m(NumRecoverableFragments), m_encoder(255, 207) + { + if (m_m > 5) { + etiLog.level(warn) << + "EDI PFT: high number of recoverable fragments" + " may lead to large overhead"; + // See TS 102 821, 7.2.1 Known values, list entry for 'm' + } + } + + // Apply Reed-Solomon FEC to the AF Packet + RSPacket Protect(AFPacket af_packet); + + // Cut a RSPacket into several fragments that can be transmitted + std::vector< std::vector<uint8_t> > ProtectAndFragment(AFPacket af_packet); + + private: + unsigned int m_k; // length of RS data word + unsigned int m_m; // number of fragments that can be recovered if lost + + size_t m_num_chunks; + + ReedSolomon m_encoder; + +}; + +#endif + |