private static BitArray generateCheckWords(BitArray stuffedBits, int totalSymbolBits, int wordSize)
{
var messageSizeInWords = (stuffedBits.Size + wordSize - 1) / wordSize;
for (var i = messageSizeInWords * wordSize - stuffedBits.Size; i > 0; i--)
{
stuffedBits.appendBit(true);
}
var rs = new ReedSolomonEncoder(getGF(wordSize));
var totalSizeInFullWords = totalSymbolBits / wordSize;
var messageWords = bitsToWords(stuffedBits, wordSize, totalSizeInFullWords);
rs.encode(messageWords, totalSizeInFullWords - messageSizeInWords);
var startPad = totalSymbolBits % wordSize;
var messageBits = new BitArray();
messageBits.appendBits(0, startPad);
foreach (var messageWord in messageWords)
{
messageBits.appendBits(messageWord, wordSize);
}
return(messageBits);
}
private static BitArray generateCheckWords(BitArray bitArray, int totalBits, int wordSize)
{
if (bitArray.Size % wordSize != 0)
{
throw new InvalidOperationException("size of bit array is not a multiple of the word size");
}
// bitArray is guaranteed to be a multiple of the wordSize, so no padding needed
int messageSizeInWords = bitArray.Size / wordSize;
var rs = new ReedSolomonEncoder(getGF(wordSize));
var totalWords = totalBits / wordSize;
var messageWords = bitsToWords(bitArray, wordSize, totalWords);
rs.encode(messageWords, totalWords - messageSizeInWords);
var startPad = totalBits % wordSize;
var messageBits = new BitArray();
messageBits.appendBits(0, startPad);
foreach (var messageWord in messageWords)
{
messageBits.appendBits(messageWord, wordSize);
}
return(messageBits);
}
/// <summary>
/// Вызов метода кодирования для текущего выбранного алгоритма коррекции ошибок
/// </summary>
/// <param name="input">Входной поток данных</param>
/// <param name="output">Выходной поток данных</param>
public void Forward(Stream input, Stream output)
{
int codeSize = _codeSize;
int dataSize = _dataSize;
int twoS = Math.Abs(codeSize - dataSize);
Debug.Assert(codeSize > dataSize);
switch (_eccId)
{
case EccId.None:
None.Forward(input, output);
break;
case EccId.ReedSolomon:
var buffer = new byte[Math.Max(codeSize, dataSize)];
while (input.Read(buffer, 0, dataSize) > 0)
{
int[] array = buffer.Select(x => (int)x).ToArray();
RsEncoder.encode(array, twoS);
output.Write(array.Select(x => (byte)x).ToArray(), 0, codeSize);
}
break;
default:
throw new NotImplementedException();
}
}
private static void testEncodeDecodeRandom(GenericGF field, int dataSize, int ecSize)
{
Assert.IsTrue(dataSize > 0 && dataSize <= field.Size - 3, "Invalid data size for " + field);
Assert.IsTrue(ecSize > 0 && ecSize + dataSize <= field.Size, "Invalid ECC size for " + field);
ReedSolomonEncoder encoder = new ReedSolomonEncoder(field);
int[] message = new int[dataSize + ecSize];
int[] dataWords = new int[dataSize];
int[] ecWords = new int[ecSize];
Random random = getPseudoRandom();
int iterations = field.Size > 256 ? 1 : DECODER_RANDOM_TEST_ITERATIONS;
for (int i = 0; i < iterations; i++)
{
// generate random data
for (int k = 0; k < dataSize; k++)
{
dataWords[k] = random.Next(field.Size);
}
// generate ECC words
Array.Copy(dataWords, 0, message, 0, dataWords.Length);
encoder.encode(message, ecWords.Length);
Array.Copy(message, dataSize, ecWords, 0, ecSize);
// check to see if Decoder can fix up to ecWords/2 random errors
testDecoder(field, dataWords, ecWords);
}
}
public void testQRCodeVersusDecoder()
{
var random = getRandom();
var encoder = new ReedSolomonEncoder(GenericGF.QR_CODE_FIELD_256);
var decoder = new ReedSolomonDecoder(GenericGF.QR_CODE_FIELD_256);
for (var i = 0; i < 100; i++)
{
var size = 2 + random.Next(254);
var toEncode = new int[size];
var ecBytes = 1 + random.Next(2 * (1 + size / 8));
ecBytes = Math.Min(ecBytes, size - 1);
var dataBytes = size - ecBytes;
for (int j = 0; j < dataBytes; j++)
{
toEncode[j] = random.Next(256);
}
var original = new int[dataBytes];
Array.Copy(toEncode, 0, original, 0, dataBytes);
encoder.encode(toEncode, ecBytes);
corrupt(toEncode, ecBytes / 2, random);
Assert.IsTrue(decoder.decode(toEncode, ecBytes));
assertArraysEqual(original, 0, toEncode, 0, dataBytes);
}
}
private static void testEncoder(GenericGF field, int[] dataWords, int[] ecWords)
{
ReedSolomonEncoder encoder = new ReedSolomonEncoder(field);
int[] messageExpected = new int[dataWords.Length + ecWords.Length];
int[] message = new int[dataWords.Length + ecWords.Length];
Array.Copy(dataWords, 0, messageExpected, 0, dataWords.Length);
Array.Copy(ecWords, 0, messageExpected, dataWords.Length, ecWords.Length);
Array.Copy(dataWords, 0, message, 0, dataWords.Length);
encoder.encode(message, ecWords.Length);
assertDataEquals("Encode in " + field + " (" + dataWords.Length + ',' + ecWords.Length + ") failed",
messageExpected, message);
}
public static bool[] MarshallInt(uint value)
{
int[] byteArray = new int[32];
byteArray[0] = (byte)(value % 256);
byteArray[1] = (byte)((value >> 8) % 256);
byteArray[2] = (byte)((value >> 16) % 256);
byteArray[3] = (byte)((value >> 24) % 256);
ReedSolomonEncoder rse = new ReedSolomonEncoder(GenericGF.QR_CODE_FIELD_256);
rse.encode(byteArray, 28);
return(UnpackByteArray(byteArray));
}
public byte[] Encode(byte[] data, int parity)
{
int[] intar = new int[data.Length + parity];
for (int i = 0; i < data.Length; i++)
{
intar[i] = data[i];
}
encoder.encode(intar, parity);
var result = new byte[intar.Length];
for (int i = 0; i < intar.Length; i++)
{
result[i] = (byte)intar[i];
}
return(result);
}
public int[] EncodeRawBytesArray(int[] data)
{
var length = data.Length * _messageLength / _informationLength;
length += (255 - (length % 255)) % 255;
var modifiedData = new int[length];
var processedBytes = 0;
for (var i = 0; i < data.Length; i += _informationLength)
{
var tempData = new int[_messageLength];
var remainder = (data.Length - i < _informationLength) ? data.Length - i : _informationLength;
for (var j = 0; j < remainder; j++)
{
tempData[j] = data[i + j];
}
for (var j = remainder; j < tempData.Length; j++)
{
tempData[j] = 0;
}
_reedSolomonEncoder.encode(tempData, _correctionLength);
remainder = remainder >= _informationLength ? _messageLength : modifiedData.Length - processedBytes;
for (var j = 0; j < remainder; j++)
{
modifiedData[processedBytes + j] = tempData[j];
}
processedBytes += _messageLength;
}
return(modifiedData);
}
/// <summary>
/// Encode using Reed-Solomon error correction (with n bytes added to the end of bits). </summary>
public static Bits bitsReedSolomonEncode(Bits bits, int n)
{
int tmpSize = (bits.size() + 7) / 8 + n;
int[] data = new int[tmpSize];
if (tmpSize > bits.Bytes.Length)
{
tmpSize = bits.Bytes.Length;
}
Array.Copy(bits.Bytes, 0, data, 0, tmpSize);
ReedSolomonEncoder enc = new ReedSolomonEncoder(GenericGF.QR_CODE_FIELD_256);
enc.encode(data, n);
Bits result = new Bits(bits);
for (int i = data.Length - n; i < data.Length; i++)
{
result.addValue(data[i], 8);
}
return(result);
}
private static void testEncoder(GenericGF field, int[] dataWords, int[] ecWords)
{
ReedSolomonEncoder encoder = new ReedSolomonEncoder(field);
int[] messageExpected = new int[dataWords.Length + ecWords.Length];
int[] message = new int[dataWords.Length + ecWords.Length];
Array.Copy(dataWords, 0, messageExpected, 0, dataWords.Length);
Array.Copy(ecWords, 0, messageExpected, dataWords.Length, ecWords.Length);
Array.Copy(dataWords, 0, message, 0, dataWords.Length);
encoder.encode(message, ecWords.Length);
assertDataEquals("Encode in " + field + " (" + dataWords.Length + ',' + ecWords.Length + ") failed",
messageExpected, message);
}
private static void testEncodeDecodeRandom(GenericGF field, int dataSize, int ecSize)
{
Assert.IsTrue(dataSize > 0 && dataSize <= field.Size - 3, "Invalid data size for " + field);
Assert.IsTrue(ecSize > 0 && ecSize + dataSize <= field.Size, "Invalid ECC size for " + field);
ReedSolomonEncoder encoder = new ReedSolomonEncoder(field);
int[] message = new int[dataSize + ecSize];
int[] dataWords = new int[dataSize];
int[] ecWords = new int[ecSize];
Random random = getPseudoRandom();
int iterations = field.Size > 256 ? 1 : DECODER_RANDOM_TEST_ITERATIONS;
for (int i = 0; i < iterations; i++)
{
// generate random data
for (int k = 0; k < dataSize; k++)
{
dataWords[k] = random.Next(field.Size);
}
// generate ECC words
Array.Copy(dataWords, 0, message, 0, dataWords.Length);
encoder.encode(message, ecWords.Length);
Array.Copy(message, dataSize, ecWords, 0, ecSize);
// check to see if Decoder can fix up to ecWords/2 random errors
testDecoder(field, dataWords, ecWords);
}
}
/// <summary>
/// Encodes the given binary content as an Aztec symbol
/// </summary>
/// <param name="data">input data string</param>
/// <param name="minECCPercent">minimal percentange of error check words (According to ISO/IEC 24778:2008,
/// a minimum of 23% + 3 words is recommended)</param>
/// <returns>Aztec symbol matrix with metadata</returns>
public static AztecCode encode(byte[] data, int minECCPercent)
{
// High-level encode
var bits = highLevelEncode(data);
// stuff bits and choose symbol size
int eccBits = bits.Size * minECCPercent / 100 + 11;
int totalSizeBits = bits.Size + eccBits;
int layers;
int wordSize = 0;
int totalSymbolBits = 0;
BitArray stuffedBits = null;
for (layers = 1; layers < NB_BITS_COMPACT.Length; layers++)
{
if (NB_BITS_COMPACT[layers] >= totalSizeBits)
{
if (wordSize != WORD_SIZE[layers])
{
wordSize = WORD_SIZE[layers];
stuffedBits = stuffBits(bits, wordSize);
}
totalSymbolBits = NB_BITS_COMPACT[layers];
if (stuffedBits.Size + eccBits <= NB_BITS_COMPACT[layers])
{
break;
}
}
}
bool compact = true;
if (layers == NB_BITS_COMPACT.Length)
{
compact = false;
for (layers = 1; layers < NB_BITS.Length; layers++)
{
if (NB_BITS[layers] >= totalSizeBits)
{
if (wordSize != WORD_SIZE[layers])
{
wordSize = WORD_SIZE[layers];
stuffedBits = stuffBits(bits, wordSize);
}
totalSymbolBits = NB_BITS[layers];
if (stuffedBits.Size + eccBits <= NB_BITS[layers])
{
break;
}
}
}
}
if (layers == NB_BITS.Length)
{
throw new ArgumentException("Data too large for an Aztec code");
}
// pad the end
int messageSizeInWords = (stuffedBits.Size + wordSize - 1) / wordSize;
for (int i = messageSizeInWords * wordSize - stuffedBits.Size; i > 0; i--)
{
stuffedBits.appendBit(true);
}
// generate check words
var rs = new ReedSolomonEncoder(getGF(wordSize));
var totalSizeInFullWords = totalSymbolBits / wordSize;
var messageWords = bitsToWords(stuffedBits, wordSize, totalSizeInFullWords);
rs.encode(messageWords, totalSizeInFullWords - messageSizeInWords);
// convert to bit array and pad in the beginning
var startPad = totalSymbolBits % wordSize;
var messageBits = new BitArray();
messageBits.appendBits(0, startPad);
foreach (var messageWord in messageWords)
{
messageBits.appendBits(messageWord, wordSize);
}
// generate mode message
var modeMessage = generateModeMessage(compact, layers, messageSizeInWords);
// allocate symbol
var baseMatrixSize = compact ? 11 + layers * 4 : 14 + layers * 4; // not including alignment lines
var alignmentMap = new int[baseMatrixSize];
int matrixSize;
if (compact)
{
// no alignment marks in compact mode, alignmentMap is a no-op
matrixSize = baseMatrixSize;
for (int i = 0; i < alignmentMap.Length; i++)
{
alignmentMap[i] = i;
}
}
else
{
matrixSize = baseMatrixSize + 1 + 2 * ((baseMatrixSize / 2 - 1) / 15);
int origCenter = baseMatrixSize / 2;
int center = matrixSize / 2;
for (int i = 0; i < origCenter; i++)
{
int newOffset = i + i / 15;
alignmentMap[origCenter - i - 1] = center - newOffset - 1;
alignmentMap[origCenter + i] = center + newOffset + 1;
}
}
var matrix = new BitMatrix(matrixSize);
// draw mode and data bits
for (int i = 0, rowOffset = 0; i < layers; i++)
{
int rowSize = compact ? (layers - i) * 4 + 9 : (layers - i) * 4 + 12;
for (int j = 0; j < rowSize; j++)
{
int columnOffset = j * 2;
for (int k = 0; k < 2; k++)
{
if (messageBits[rowOffset + columnOffset + k])
{
matrix[alignmentMap[i * 2 + k], alignmentMap[i * 2 + j]] = true;
}
if (messageBits[rowOffset + rowSize * 2 + columnOffset + k])
{
matrix[alignmentMap[i * 2 + j], alignmentMap[baseMatrixSize - 1 - i * 2 - k]] = true;
}
if (messageBits[rowOffset + rowSize * 4 + columnOffset + k])
{
matrix[alignmentMap[baseMatrixSize - 1 - i * 2 - k], alignmentMap[baseMatrixSize - 1 - i * 2 - j]] = true;
}
if (messageBits[rowOffset + rowSize * 6 + columnOffset + k])
{
matrix[alignmentMap[baseMatrixSize - 1 - i * 2 - j], alignmentMap[i * 2 + k]] = true;
}
}
}
rowOffset += rowSize * 8;
}
drawModeMessage(matrix, compact, matrixSize, modeMessage);
// draw alignment marks
if (compact)
{
drawBullsEye(matrix, matrixSize / 2, 5);
}
else
{
drawBullsEye(matrix, matrixSize / 2, 7);
for (int i = 0, j = 0; i < baseMatrixSize / 2 - 1; i += 15, j += 16)
{
for (int k = (matrixSize / 2) & 1; k < matrixSize; k += 2)
{
matrix[matrixSize / 2 - j, k] = true;
matrix[matrixSize / 2 + j, k] = true;
matrix[k, matrixSize / 2 - j] = true;
matrix[k, matrixSize / 2 + j] = true;
}
}
}
return(new AztecCode
{
isCompact = compact,
Size = matrixSize,
Layers = layers,
CodeWords = messageSizeInWords,
Matrix = matrix
});
}