// Embed position detection patterns and surrounding vertical/horizontal separators.
private static void EmbedPositionDetectionPatternsAndSeparators(ByteMatrix matrix)
{
// Embed three big squares at corners.
int pdpWidth = POSITION_DETECTION_PATTERN[0].Length;
// Left top corner.
EmbedPositionDetectionPattern(0, 0, matrix);
// Right top corner.
EmbedPositionDetectionPattern(matrix.GetWidth() - pdpWidth, 0, matrix);
// Left bottom corner.
EmbedPositionDetectionPattern(0, matrix.GetWidth() - pdpWidth, matrix);
// Embed horizontal separation patterns around the squares.
int hspWidth = HORIZONTAL_SEPARATION_PATTERN[0].Length;
// Left top corner.
EmbedHorizontalSeparationPattern(0, hspWidth - 1, matrix);
// Right top corner.
EmbedHorizontalSeparationPattern(matrix.GetWidth() - hspWidth,
hspWidth - 1, matrix);
// Left bottom corner.
EmbedHorizontalSeparationPattern(0, matrix.GetWidth() - hspWidth, matrix);
// Embed vertical separation patterns around the squares.
int vspSize = VERTICAL_SEPARATION_PATTERN.Length;
// Left top corner.
EmbedVerticalSeparationPattern(vspSize, 0, matrix);
// Right top corner.
EmbedVerticalSeparationPattern(matrix.GetHeight() - vspSize - 1, 0, matrix);
// Left bottom corner.
EmbedVerticalSeparationPattern(vspSize, matrix.GetHeight() - vspSize,
matrix);
}
// Helper function for applyMaskPenaltyRule1. We need this for doing this calculation in both
// vertical and horizontal orders respectively.
private static int ApplyMaskPenaltyRule1Internal(ByteMatrix matrix, bool isHorizontal)
{
int penalty = 0;
int numSameBitCells = 0;
int prevBit = -1;
// Horizontal mode:
// for (int i = 0; i < matrix.Height(); ++i) {
// for (int j = 0; j < matrix.Width(); ++j) {
// int bit = matrix.Get(i, j);
// Vertical mode:
// for (int i = 0; i < matrix.Width(); ++i) {
// for (int j = 0; j < matrix.Height(); ++j) {
// int bit = matrix.Get(j, i);
int iLimit = isHorizontal ? matrix.GetHeight() : matrix.GetWidth();
int jLimit = isHorizontal ? matrix.GetWidth() : matrix.GetHeight();
sbyte[][] array = matrix.GetArray();
for (int i = 0; i < iLimit; ++i)
{
for (int j = 0; j < jLimit; ++j)
{
int bit = isHorizontal ? array[i][j] : array[j][i];
if (bit == prevBit)
{
numSameBitCells += 1;
// Found five repetitive cells with the same color (bit).
// We'll give penalty of 3.
if (numSameBitCells == 5)
{
penalty += 3;
}
else if (numSameBitCells > 5)
{
// After five repetitive cells, we'll add the penalty one
// by one.
penalty += 1;
}
}
else
{
numSameBitCells = 1; // Include the cell itself.
prevBit = bit;
}
}
numSameBitCells = 0; // Clear at each row/column.
}
return(penalty);
}
private static void EmbedTimingPatterns(ByteMatrix matrix)
{
// -8 is for skipping position detection patterns (size 7), and two horizontal/vertical
// separation patterns (size 1). Thus, 8 = 7 + 1.
for (int i = 8; i < matrix.GetWidth() - 8; ++i)
{
int bit = (i + 1) % 2;
// Horizontal line.
if (!IsValidValue(matrix.Get(i, 6)))
{
throw new WriterException();
}
if (IsEmpty(matrix.Get(i, 6)))
{
matrix.Set(i, 6, bit);
}
// Vertical line.
if (!IsValidValue(matrix.Get(6, i)))
{
throw new WriterException();
}
if (IsEmpty(matrix.Get(6, i)))
{
matrix.Set(6, i, bit);
}
}
}
// Embed "dataBits" using "getMaskPattern". On success, modify the matrix and return true.
// For debugging purposes, it skips masking process if "getMaskPattern" is -1.
// See 8.7 of JISX0510:2004 (p.38) for how to embed data bits.
public static void EmbedDataBits(BitVector dataBits, int maskPattern, ByteMatrix matrix)
{
int bitIndex = 0;
int direction = -1;
// Start from the right bottom cell.
int x = matrix.GetWidth() - 1;
int y = matrix.GetHeight() - 1;
while (x > 0)
{
// Skip the vertical timing pattern.
if (x == 6)
{
x -= 1;
}
while (y >= 0 && y < matrix.GetHeight())
{
for (int i = 0; i < 2; ++i)
{
int xx = x - i;
// Skip the cell if it's not empty.
if (!IsEmpty(matrix.Get(xx, y)))
{
continue;
}
int bit;
if (bitIndex < dataBits.Size())
{
bit = dataBits.At(bitIndex);
++bitIndex;
}
else
{
// Padding bit. If there is no bit left, we'll fill the left cells with 0, as described
// in 8.4.9 of JISX0510:2004 (p. 24).
bit = 0;
}
// Skip masking if mask_pattern is -1.
if (maskPattern != -1)
{
if (MaskUtil.GetDataMaskBit(maskPattern, xx, y))
{
bit ^= 0x1;
}
}
matrix.Set(xx, y, bit);
}
y += direction;
}
direction = -direction; // Reverse the direction.
y += direction;
x -= 2; // Move to the left.
}
// All bits should be consumed.
if (bitIndex != dataBits.Size())
{
throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.Size());
}
}
// Embed type information. On success, modify the matrix.
public static void EmbedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
{
BitVector typeInfoBits = new BitVector();
MakeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
for (int i = 0; i < typeInfoBits.Size(); ++i)
{
// Place bits in LSB to MSB order. LSB (least significant bit) is the last value in
// "typeInfoBits".
int bit = typeInfoBits.At(typeInfoBits.Size() - 1 - i);
// Type info bits at the left top corner. See 8.9 of JISX0510:2004 (p.46).
int x1 = TYPE_INFO_COORDINATES[i][0];
int y1 = TYPE_INFO_COORDINATES[i][1];
matrix.Set(x1, y1, bit);
if (i < 8)
{
// Right top corner.
int x2 = matrix.GetWidth() - i - 1;
int y2 = 8;
matrix.Set(x2, y2, bit);
}
else
{
// Left bottom corner.
int x2 = 8;
int y2 = matrix.GetHeight() - 7 + (i - 8);
matrix.Set(x2, y2, bit);
}
}
}
// Apply mask penalty rule 3 and return the penalty. Find consecutive cells of 00001011101 or
// 10111010000, and give penalty to them. If we find patterns like 000010111010000, we give
// penalties twice (i.e. 40 * 2).
public static int ApplyMaskPenaltyRule3(ByteMatrix matrix)
{
int penalty = 0;
sbyte[][] array = matrix.GetArray();
int width = matrix.GetWidth();
int height = matrix.GetHeight();
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
// Tried to simplify following conditions but failed.
if (x + 6 < width &&
array[y][x] == 1 &&
array[y][x + 1] == 0 &&
array[y][x + 2] == 1 &&
array[y][x + 3] == 1 &&
array[y][x + 4] == 1 &&
array[y][x + 5] == 0 &&
array[y][x + 6] == 1 &&
((x + 10 < width &&
array[y][x + 7] == 0 &&
array[y][x + 8] == 0 &&
array[y][x + 9] == 0 &&
array[y][x + 10] == 0) ||
(x - 4 >= 0 &&
array[y][x - 1] == 0 &&
array[y][x - 2] == 0 &&
array[y][x - 3] == 0 &&
array[y][x - 4] == 0)))
{
penalty += 40;
}
if (y + 6 < height &&
array[y][x] == 1 &&
array[y + 1][x] == 0 &&
array[y + 2][x] == 1 &&
array[y + 3][x] == 1 &&
array[y + 4][x] == 1 &&
array[y + 5][x] == 0 &&
array[y + 6][x] == 1 &&
((y + 10 < height &&
array[y + 7][x] == 0 &&
array[y + 8][x] == 0 &&
array[y + 9][x] == 0 &&
array[y + 10][x] == 0) ||
(y - 4 >= 0 &&
array[y - 1][x] == 0 &&
array[y - 2][x] == 0 &&
array[y - 3][x] == 0 &&
array[y - 4][x] == 0)))
{
penalty += 40;
}
}
}
return(penalty);
}
// Checks all the member variables are set properly. Returns true on success. Otherwise, returns
// false.
public bool IsValid()
{
return
// First check if all version are not uninitialized.
(mode != null &&
ecLevel != null &&
version != -1 &&
matrixWidth != -1 &&
maskPattern != -1 &&
numTotalBytes != -1 &&
numDataBytes != -1 &&
numECBytes != -1 &&
numRSBlocks != -1 &&
// Then check them in other ways..
IsValidMaskPattern(maskPattern) &&
numTotalBytes == numDataBytes + numECBytes &&
// ByteMatrix stuff.
matrix != null &&
matrixWidth == matrix.GetWidth() &&
// See 7.3.1 of JISX0510:2004 (p.5).
matrix.GetWidth() == matrix.GetHeight()); // Must be square.
}
private byte[] GetBitMatrix()
{
int width = bm.GetWidth();
int height = bm.GetHeight();
int stride = (width + 7) / 8;
byte[] b = new byte[stride * height];
sbyte[][] mt = bm.GetArray();
for (int y = 0; y < height; ++y)
{
sbyte[] line = mt[y];
for (int x = 0; x < width; ++x)
{
if (line[x] != 0)
{
int offset = stride * y + x / 8;
b[offset] |= (byte)(0x80 >> (x % 8));
}
}
}
return(b);
}
// Apply mask penalty rule 4 and return the penalty. Calculate the ratio of dark cells and give
// penalty if the ratio is far from 50%. It gives 10 penalty for 5% distance. Examples:
// - 0% => 100
// - 40% => 20
// - 45% => 10
// - 50% => 0
// - 55% => 10
// - 55% => 20
// - 100% => 100
public static int ApplyMaskPenaltyRule4(ByteMatrix matrix)
{
int numDarkCells = 0;
sbyte[][] array = matrix.GetArray();
int width = matrix.GetWidth();
int height = matrix.GetHeight();
for (int y = 0; y < height; ++y)
{
for (int x = 0; x < width; ++x)
{
if (array[y][x] == 1)
{
numDarkCells += 1;
}
}
}
int numTotalCells = matrix.GetHeight() * matrix.GetWidth();
double darkRatio = (double)numDarkCells / numTotalCells;
return(Math.Abs((int)(darkRatio * 100 - 50)) / 5 * 10);
}
// Apply mask penalty rule 2 and return the penalty. Find 2x2 blocks with the same color and give
// penalty to them.
public static int ApplyMaskPenaltyRule2(ByteMatrix matrix)
{
int penalty = 0;
sbyte[][] array = matrix.GetArray();
int width = matrix.GetWidth();
int height = matrix.GetHeight();
for (int y = 0; y < height - 1; ++y)
{
for (int x = 0; x < width - 1; ++x)
{
int value = array[y][x];
if (value == array[y][x + 1] && value == array[y + 1][x] && value == array[y + 1][x + 1])
{
penalty += 3;
}
}
}
return(penalty);
}
// Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
// 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
private static ByteMatrix RenderResult(QRCode code, int width, int height)
{
ByteMatrix input = code.GetMatrix();
int inputWidth = input.GetWidth();
int inputHeight = input.GetHeight();
int qrWidth = inputWidth + (QUIET_ZONE_SIZE << 1);
int qrHeight = inputHeight + (QUIET_ZONE_SIZE << 1);
int outputWidth = Math.Max(width, qrWidth);
int outputHeight = Math.Max(height, qrHeight);
int multiple = Math.Min(outputWidth / qrWidth, outputHeight / qrHeight);
// Padding includes both the quiet zone and the extra white pixels to accommodate the requested
// dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
// If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
// handle all the padding from 100x100 (the actual QR) up to 200x160.
int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;
int topPadding = (outputHeight - (inputHeight * multiple)) / 2;
ByteMatrix output = new ByteMatrix(outputWidth, outputHeight);
sbyte[][] outputArray = output.GetArray();
// We could be tricky and use the first row in each set of multiple as the temporary storage,
// instead of allocating this separate array.
sbyte[] row = new sbyte[outputWidth];
// 1. Write the white lines at the top
for (int y = 0; y < topPadding; y++)
{
SetRowColor(outputArray[y], (sbyte)-1);
}
// 2. Expand the QR image to the multiple
sbyte[][] inputArray = input.GetArray();
for (int y = 0; y < inputHeight; y++)
{
// a. Write the white pixels at the left of each row
for (int x = 0; x < leftPadding; x++)
{
row[x] = (sbyte)-1;
}
// b. Write the contents of this row of the barcode
int offset = leftPadding;
for (int x = 0; x < inputWidth; x++)
{
sbyte value = (inputArray[y][x] == 1) ? (sbyte)0 : (sbyte)-1;
for (int z = 0; z < multiple; z++)
{
row[offset + z] = value;
}
offset += multiple;
}
// c. Write the white pixels at the right of each row
offset = leftPadding + (inputWidth * multiple);
for (int x = offset; x < outputWidth; x++)
{
row[x] = (sbyte)-1;
}
// d. Write the completed row multiple times
offset = topPadding + (y * multiple);
for (int z = 0; z < multiple; z++)
{
System.Array.Copy(row, 0, outputArray[offset + z], 0, outputWidth);
}
}
// 3. Write the white lines at the bottom
int offset2 = topPadding + (inputHeight * multiple);
for (int y = offset2; y < outputHeight; y++)
{
SetRowColor(outputArray[y], (sbyte)-1);
}
return(output);
}