DataMatrixDecoder.cpp Example File
appdemos/qtws/QZXing/zxing/zxing/datamatrix/decoder/DataMatrixDecoder.cpp
#include <zxing/datamatrix/decoder/Decoder.h>
#include <zxing/datamatrix/decoder/BitMatrixParser.h>
#include <zxing/datamatrix/decoder/DataBlock.h>
#include <zxing/datamatrix/decoder/DecodedBitStreamParser.h>
#include <zxing/datamatrix/Version.h>
#include <zxing/ReaderException.h>
#include <zxing/ChecksumException.h>
#include <zxing/common/reedsolomon/ReedSolomonException.h>
using zxing::Ref;
using zxing::DecoderResult;
using zxing::ArrayRef;
using zxing::BitMatrix;
namespace zxing {
namespace datamatrix {
Decoder::Decoder() : rsDecoder_(GenericGF::DATA_MATRIX_FIELD_256) {}
void Decoder::correctErrors(ArrayRef<byte> codewordBytes, int numDataCodewords) {
int numCodewords = codewordBytes->size();
ArrayRef<int> codewordInts(numCodewords);
for (int i = 0; i < numCodewords; i++) {
codewordInts[i] = codewordBytes[i] & 0xff;
}
int numECCodewords = numCodewords - numDataCodewords;
try {
rsDecoder_.decode(codewordInts, numECCodewords);
} catch (ReedSolomonException const& ignored) {
(void)ignored;
throw ChecksumException();
}
for (int i = 0; i < numDataCodewords; i++) {
codewordBytes[i] = (byte)codewordInts[i];
}
}
Ref<DecoderResult> Decoder::decode(Ref<BitMatrix> bits) {
BitMatrixParser parser(bits);
Version *version = parser.readVersion(bits);
ArrayRef<byte> codewords(parser.readCodewords());
std::vector<Ref<DataBlock> > dataBlocks = DataBlock::getDataBlocks(codewords, version);
int dataBlocksCount = dataBlocks.size();
int totalBytes = 0;
for (int i = 0; i < dataBlocksCount; i++) {
totalBytes += dataBlocks[i]->getNumDataCodewords();
}
ArrayRef<byte> resultBytes(totalBytes);
for (int j = 0; j < dataBlocksCount; j++) {
Ref<DataBlock> dataBlock(dataBlocks[j]);
ArrayRef<byte> codewordBytes = dataBlock->getCodewords();
int numDataCodewords = dataBlock->getNumDataCodewords();
correctErrors(codewordBytes, numDataCodewords);
for (int i = 0; i < numDataCodewords; i++) {
resultBytes[i * dataBlocksCount + j] = codewordBytes[i];
}
}
DecodedBitStreamParser decodedBSParser;
return Ref<DecoderResult> (decodedBSParser.decode(resultBytes));
}
}
}