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Diffstat (limited to 'src/ConvEncoder.cpp')
| -rw-r--r-- | src/ConvEncoder.cpp | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/src/ConvEncoder.cpp b/src/ConvEncoder.cpp new file mode 100644 index 0000000..109b51a --- /dev/null +++ b/src/ConvEncoder.cpp @@ -0,0 +1,150 @@ +/* + 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 CRC-DADMOD. + + CRC-DADMOD 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-DADMOD 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-DADMOD. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "ConvEncoder.h" +#include "PcDebug.h" + +#include <stdlib.h> +#include <stdio.h> +#include <stdexcept> + + +const static unsigned char PARITY[] = { + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, + 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 +}; + + +ConvEncoder::ConvEncoder(size_t framesize) : + ModCodec(ModFormat(framesize), ModFormat((framesize * 4) + 3)), + d_framesize(framesize) +{ + PDEBUG("ConvEncoder::ConvEncoder(%zu)\n", framesize); + +} + + +ConvEncoder::~ConvEncoder() +{ + PDEBUG("ConvEncoder::~ConvEncoder()\n"); + +} + + +int ConvEncoder::process(Buffer* const dataIn, Buffer* dataOut) +{ + PDEBUG("ConvEncoder::process" + "(dataIn: %p, dataOut: %p)\n", + dataIn, dataOut); + + size_t in_block_size = d_framesize; + size_t out_block_size = (d_framesize * 4) + 3; + size_t in_offset = 0; + size_t out_offset = 0; + unsigned short memory = 0; + unsigned char data; + + if (dataIn->getLength() != in_block_size) { + PDEBUG("%zu != %zu != 0\n", dataIn->getLength(), in_block_size); + throw std::runtime_error( + "ConvEncoder::process input size not valid!\n"); + } + dataOut->setLength(out_block_size); + const unsigned char* in = reinterpret_cast<const unsigned char*>(dataIn->getData()); + unsigned char* out = reinterpret_cast<unsigned char*>(dataOut->getData()); + + // While there is enought input and ouput items + while (dataIn->getLength() - in_offset >= in_block_size && + dataOut->getLength() - out_offset >= out_block_size) { + for (size_t in_count = 0; in_count < in_block_size; ++in_count) { + data = in[in_offset]; + //PDEBUG("Input: 0x%x\n", data); + // For next 4 output bytes + for (unsigned out_count = 0; out_count < 4; ++out_count) { + out[out_offset] = 0; + // For each 4-bit output word + for (unsigned j = 0; j < 2; ++j) { + memory >>= 1; + memory |= (data >> 7) << 6; + data <<= 1; + //PDEBUG("Memory: 0x%x\n", memory); + unsigned char poly[4] = { + memory & 0x5b, + memory & 0x79, + memory & 0x65, + memory & 0x5b + }; + //PDEBUG("Polys: 0x%x, 0x%x, 0x%x, 0x%x\n", poly[0], poly[1], poly[2], poly[3]); + // For each poly + for (unsigned k = 0; k < 4; ++k) { + out[out_offset] <<= 1; + out[out_offset] |= PARITY[poly[k]]; + //PDEBUG("Out bit: %i\n", out[no] >> 7); + } + } + //PDEBUG("Out: 0x%x\n", out[no]); + ++out_offset; + } + ++in_offset; + } + for (unsigned pad_count = 0; pad_count < 3; ++pad_count) { + out[out_offset] = 0; + // For each 4-bit output word + for (unsigned j = 0; j < 2; ++j) { + memory >>= 1; + //PDEBUG("Memory: 0x%x\n", memory); + unsigned char poly[4] = { + memory & 0x5b, + memory & 0x79, + memory & 0x65, + memory & 0x5b + }; + //PDEBUG("Polys: 0x%x, 0x%x, 0x%x, 0x%x\n", poly[0], poly[1], poly[2], poly[3]); + // For each poly + for (unsigned k = 0; k < 4; ++k) { + out[out_offset] <<= 1; + out[out_offset] |= PARITY[poly[k]]; + //PDEBUG("Out bit: %i\n", out[no] >> 7); + } + } + //PDEBUG("Out: 0x%x\n", out[no]); + ++out_offset; + } + } + + PDEBUG(" Consume: %zu\n", in_offset); + PDEBUG(" Return: %zu\n", out_offset); + return out_offset; +} |