// Embed position detection patterns and surrounding vertical/horizontal separators.
private static void embedPositionDetectionPatternsAndSeparators(ByteMatrix matrix)
throws WriterException {
// 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);
}
private static void embedPositionDetectionPatternsAndSeparators(ByteMatrix matrix)
throws WriterException {
int pdpWidth = POSITION_DETECTION_PATTERN[0].length;
embedPositionDetectionPattern(0, 0, matrix);
embedPositionDetectionPattern(matrix.getWidth() - pdpWidth, 0, matrix);
embedPositionDetectionPattern(0, matrix.getWidth() - pdpWidth, matrix);
int hspWidth = HORIZONTAL_SEPARATION_PATTERN[0].length;
embedHorizontalSeparationPattern(0, hspWidth - 1, matrix);
embedHorizontalSeparationPattern(matrix.getWidth() - hspWidth, hspWidth - 1, matrix);
embedHorizontalSeparationPattern(0, matrix.getWidth() - hspWidth, matrix);
int vspSize = VERTICAL_SEPARATION_PATTERN.length;
embedVerticalSeparationPattern(vspSize, 0, matrix);
embedVerticalSeparationPattern(matrix.getHeight() - vspSize - 1, 0, matrix);
embedVerticalSeparationPattern(vspSize, matrix.getHeight() - vspSize, matrix);
}
// 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.
static void embedDataBits(BitArray dataBits, int maskPattern, ByteMatrix matrix)
throws WriterException {
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;
}
boolean bit;
if (bitIndex < dataBits.getSize()) {
bit = dataBits.get(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 = false;
}
// Skip masking if mask_pattern is -1.
if (maskPattern != -1) {
if (MaskUtil.getDataMaskBit(maskPattern, xx, y)) {
bit = !bit;
}
}
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.getSize()) {
throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.getSize());
}
}
static void embedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
throws WriterException {
BitArray typeInfoBits = new BitArray();
makeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
for (int i = 0; i < typeInfoBits.getSize(); ++i) {
boolean bit = typeInfoBits.get(typeInfoBits.getSize() - 1 - i);
int x1 = TYPE_INFO_COORDINATES[i][0];
int y1 = TYPE_INFO_COORDINATES[i][1];
matrix.set(x1, y1, bit);
if (i < 8) {
int x2 = matrix.getWidth() - i - 1;
int y2 = 8;
matrix.set(x2, y2, bit);
} else {
int x2 = 8;
int y2 = matrix.getHeight() - 7 + (i - 8);
matrix.set(x2, y2, bit);
}
}
}
// 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;
byte[][] 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;
}
// Embed type information. On success, modify the matrix.
public static void embedTypeInfo(ErrorCorrectionLevel ecLevel, int maskPattern, ByteMatrix matrix)
throws WriterException {
BitArray typeInfoBits = new BitArray();
makeTypeInfoBits(ecLevel, maskPattern, typeInfoBits);
for (int i = 0; i < typeInfoBits.getSize(); ++i) {
// Place bits in LSB to MSB order. LSB (least significant bit) is the last value in
// "typeInfoBits".
boolean bit = typeInfoBits.get(typeInfoBits.getSize() - 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);
}
}
}
static void embedDataBits(BitArray dataBits, int maskPattern, ByteMatrix matrix)
throws WriterException {
int bitIndex = 0;
int direction = -1;
int x = matrix.getWidth() - 1;
int y = matrix.getHeight() - 1;
while (x > 0) {
if (x == 6) {
x -= 1;
}
while (y >= 0 && y < matrix.getHeight()) {
for (int i = 0; i < 2; ++i) {
int xx = x - i;
if (!isEmpty(matrix.get(xx, y))) {
continue;
}
boolean bit;
if (bitIndex < dataBits.getSize()) {
bit = dataBits.get(bitIndex);
++bitIndex;
} else {
bit = false;
}
if (maskPattern != -1) {
if (MaskUtil.getDataMaskBit(maskPattern, xx, y)) {
bit = !bit;
}
}
matrix.set(xx, y, bit);
}
y += direction;
}
direction = -direction;
y += direction;
x -= 2;
}
if (bitIndex != dataBits.getSize()) {
throw new WriterException("Not all bits consumed: " + bitIndex + '/' + dataBits.getSize());
}
}
static void maybeEmbedVersionInfo(int version, ByteMatrix matrix) throws WriterException {
if (version < 7) {
return;
}
BitArray versionInfoBits = new BitArray();
makeVersionInfoBits(version, versionInfoBits);
int bitIndex = 6 * 3 - 1;
for (int i = 0; i < 6; ++i) {
for (int j = 0; j < 3; ++j) {
boolean bit = versionInfoBits.get(bitIndex);
bitIndex--;
matrix.set(i, matrix.getHeight() - 11 + j, bit);
matrix.set(matrix.getHeight() - 11 + j, i, bit);
}
}
}
// Embed version information if need be. On success, modify the matrix and return true.
// See 8.10 of JISX0510:2004 (p.47) for how to embed version information.
public static void maybeEmbedVersionInfo(int version, ByteMatrix matrix) throws WriterException {
if (version < 7) { // Version info is necessary if version >= 7.
return; // Don't need version info.
}
BitArray versionInfoBits = new BitArray();
makeVersionInfoBits(version, versionInfoBits);
int bitIndex = 6 * 3 - 1; // It will decrease from 17 to 0.
for (int i = 0; i < 6; ++i) {
for (int j = 0; j < 3; ++j) {
// Place bits in LSB (least significant bit) to MSB order.
boolean bit = versionInfoBits.get(bitIndex);
bitIndex--;
// Left bottom corner.
matrix.set(i, matrix.getHeight() - 11 + j, bit);
// Right bottom corner.
matrix.set(matrix.getHeight() - 11 + j, i, 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;
byte[][] 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;
}
// Helper function for applyMaskPenaltyRule1. We need this for doing this
// calculation in both
// vertical and horizontal orders respectively.
private static int applyMaskPenaltyRule1Internal(ByteMatrix matrix, boolean 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();
byte[][] 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;
}
// 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;
byte[][] 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;
}
public boolean isValid() {
return a != null
&& b != null
&& c != -1
&& d != -1
&& e != -1
&& f != -1
&& g != -1
&& h != -1
&& i != -1
&& isValidMaskPattern(e)
&& f == g + h
&& j != null
&& d == j.getWidth()
&& j.getWidth() == j.getHeight();
}
// 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 BitMatrix renderResult(QRCode code, int width, int height, int quietZone) {
ByteMatrix input = code.getMatrix();
if (input == null) {
throw new IllegalStateException();
}
int inputWidth = input.getWidth();
int inputHeight = input.getHeight();
int qrWidth = inputWidth + (quietZone << 1);
int qrHeight = inputHeight + (quietZone << 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;
BitMatrix output = new BitMatrix(outputWidth, outputHeight);
for (int inputY = 0, outputY = topPadding;
inputY < inputHeight;
inputY++, outputY += multiple) {
// Write the contents of this row of the barcode
for (int inputX = 0, outputX = leftPadding;
inputX < inputWidth;
inputX++, outputX += multiple) {
if (input.get(inputX, inputY) == 1) {
output.setRegion(outputX, outputY, multiple, multiple);
}
}
}
return output;
}
private static void embedDarkDotAtLeftBottomCorner(ByteMatrix matrix) throws WriterException {
if (matrix.get(8, matrix.getHeight() - 8) == 0) {
throw new WriterException();
}
matrix.set(8, matrix.getHeight() - 8, 1);
}