msb-public
/
QR-Code-generator
mirror of https://github.com/nayuki/QR-Code-generator
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Code Issues Projects Releases Wiki Activity

0527 extract method 적용 / switch 문장 Command pattern 적용할 예정

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pull/90/head
wslbal 5 years ago
parent 92b35766fb
commit 15f548220b
1 changed files with 220 additions and 212 deletions
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432
java/src/main/java/io/nayuki/qrcodegen/QrCode.java
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@ -51,9 +51,9 @@ import java.util.Objects;
* @see QrSegment
*/
public final class QrCode {
/*---- Static factory functions (high level) ----*/
/**
* Returns a QR Code representing the specified Unicode text string at the specified error correction level.
* As a conservative upper bound, this function is guaranteed to succeed for strings that have 738 or fewer
@ -73,8 +73,8 @@ public final class QrCode {
List<QrSegment> segs = QrSegment.makeSegments(text);
return encodeSegments(segs, ecl);
}
/**
* Returns a QR Code representing the specified binary data at the specified error correction level.
* This function always encodes using the binary segment mode, not any text mode. The maximum number of
@ -93,10 +93,10 @@ public final class QrCode {
QrSegment seg = QrSegment.makeBytes(data);
return encodeSegments(Arrays.asList(seg), ecl);
}
/*---- Static factory functions (mid level) ----*/
/**
* Returns a QR Code representing the specified segments at the specified error correction
* level. The smallest possible QR Code version is automatically chosen for the output. The ECC level
@ -115,8 +115,8 @@ public final class QrCode {
public static QrCode encodeSegments(List<QrSegment> segs, Ecc ecl) {
return encodeSegments(segs, ecl, MIN_VERSION, MAX_VERSION, -1, true);
}
/**
* Returns a QR Code representing the specified segments with the specified encoding parameters.
* The smallest possible QR Code version within the specified range is automatically
@ -146,7 +146,7 @@ public final class QrCode {
Objects.requireNonNull(ecl);
if (!(MIN_VERSION <= minVersion && minVersion <= maxVersion && maxVersion <= MAX_VERSION) || mask < -1 || mask > 7)
throw new IllegalArgumentException("Invalid value");
// Find the minimal version number to use
int version, dataUsedBits;
for (version = minVersion; ; version++) {
@ -162,13 +162,13 @@ public final class QrCode {
}
}
assert dataUsedBits != -1;
// Increase the error correction level while the data still fits in the current version number
for (Ecc newEcl : Ecc.values()) { // From low to high
if (boostEcl && dataUsedBits <= getNumDataCodewords(version, newEcl) * 8)
ecl = newEcl;
}
// Concatenate all segments to create the data bit string
BitBuffer bb = new BitBuffer();
for (QrSegment seg : segs) {
@ -177,62 +177,62 @@ public final class QrCode {
bb.appendData(seg.data);
}
assert bb.bitLength() == dataUsedBits;
// Add terminator and pad up to a byte if applicable
int dataCapacityBits = getNumDataCodewords(version, ecl) * 8;
assert bb.bitLength() <= dataCapacityBits;
bb.appendBits(0, Math.min(4, dataCapacityBits - bb.bitLength()));
bb.appendBits(0, (8 - bb.bitLength() % 8) % 8);
assert bb.bitLength() % 8 == 0;
// Pad with alternating bytes until data capacity is reached
for (int padByte = 0xEC; bb.bitLength() < dataCapacityBits; padByte ^= 0xEC ^ 0x11)
bb.appendBits(padByte, 8);
// Pack bits into bytes in big endian
byte[] dataCodewords = new byte[bb.bitLength() / 8];
for (int i = 0; i < bb.bitLength(); i++)
dataCodewords[i >>> 3] |= bb.getBit(i) << (7 - (i & 7));
// Create the QR Code object
return new QrCode(version, ecl, dataCodewords, mask);
}
/*---- Instance fields ----*/
// Public immutable scalar parameters:
/** The version number of this QR Code, which is between 1 and 40 (inclusive).
* This determines the size of this barcode. */
public final int version;
/** The width and height of this QR Code, measured in modules, between
* 21 and 177 (inclusive). This is equal to version &#xD7; 4 + 17. */
public final int size;
/** The error correction level used in this QR Code, which is not {@code null}. */
public final Ecc errorCorrectionLevel;
/** The index of the mask pattern used in this QR Code, which is between 0 and 7 (inclusive).
* <p>Even if a QR Code is created with automatic masking requested (mask =
* &#x2212;1), the resulting object still has a mask value between 0 and 7. */
public final int mask;
// Private grids of modules/pixels, with dimensions of size*size:
// The modules of this QR Code (false = white, true = black).
// Immutable after constructor finishes. Accessed through getModule().
private boolean[][] modules;
// Indicates function modules that are not subjected to masking. Discarded when constructor finishes.
private boolean[][] isFunction;
/*---- Constructor (low level) ----*/
/**
* Constructs a QR Code with the specified version number,
* error correction level, data codeword bytes, and mask number.
@ -258,7 +258,7 @@ public final class QrCode {
Objects.requireNonNull(dataCodewords);
modules = new boolean[size][size]; // Initially all white
isFunction = new boolean[size][size];
// Compute ECC, draw modules, do masking
drawFunctionPatterns();
byte[] allCodewords = addEccAndInterleave(dataCodewords);
@ -266,11 +266,11 @@ public final class QrCode {
this.mask = handleConstructorMasking(msk);
isFunction = null;
}
/*---- Public instance methods ----*/
/**
* Returns the color of the module (pixel) at the specified coordinates, which is {@code false}
* for white or {@code true} for black. The top left corner has the coordinates (x=0, y=0).
@ -283,8 +283,8 @@ public final class QrCode {
public boolean getModule(int x, int y) {
return 0 <= x && x < size && 0 <= y && y < size && modules[y][x];
}
/**
* Returns a raster image depicting this QR Code, with the specified module scale and border modules.
* <p>For example, toImage(scale=10, border=4) means to pad the QR Code with 4 white
@ -301,7 +301,7 @@ public final class QrCode {
throw new IllegalArgumentException("Value out of range");
if (border > Integer.MAX_VALUE / 2 || size + border * 2L > Integer.MAX_VALUE / scale)
throw new IllegalArgumentException("Scale or border too large");
BufferedImage result = new BufferedImage((size + border * 2) * scale, (size + border * 2) * scale, BufferedImage.TYPE_INT_RGB);
for (int y = 0; y < result.getHeight(); y++) {
for (int x = 0; x < result.getWidth(); x++) {
@ -311,8 +311,8 @@ public final class QrCode {
}
return result;
}
/**
* Returns a string of SVG code for an image depicting this QR Code, with the specified number
* of border modules. The string always uses Unix newlines (\n), regardless of the platform.
@ -325,12 +325,12 @@ public final class QrCode {
throw new IllegalArgumentException("Border must be non-negative");
long brd = border;
StringBuilder sb = new StringBuilder()
.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
.append("<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n")
.append(String.format("<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 %1$d %1$d\" stroke=\"none\">\n",
size + brd * 2))
.append("\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\"/>\n")
.append("\t<path d=\"");
.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
.append("<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n")
.append(String.format("<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 %1$d %1$d\" stroke=\"none\">\n",
size + brd * 2))
.append("\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\"/>\n")
.append("\t<path d=\"");
for (int y = 0; y < size; y++) {
for (int x = 0; x < size; x++) {
if (getModule(x, y)) {
@ -341,15 +341,15 @@ public final class QrCode {
}
}
return sb
.append("\" fill=\"#000000\"/>\n")
.append("</svg>\n")
.toString();
.append("\" fill=\"#000000\"/>\n")
.append("</svg>\n")
.toString();
}
/*---- Private helper methods for constructor: Drawing function modules ----*/
// Reads this object's version field, and draws and marks all function modules.
private void drawFunctionPatterns() {
// Draw horizontal and vertical timing patterns
@ -357,12 +357,12 @@ public final class QrCode {
setFunctionModule(6, i, i % 2 == 0);
setFunctionModule(i, 6, i % 2 == 0);
}
// Draw 3 finder patterns (all corners except bottom right; overwrites some timing modules)
drawFinderPattern(3, 3);
drawFinderPattern(size - 4, 3);
drawFinderPattern(3, size - 4);
// Draw numerous alignment patterns
int[] alignPatPos = getAlignmentPatternPositions();
int numAlign = alignPatPos.length;
@ -373,13 +373,13 @@ public final class QrCode {
drawAlignmentPattern(alignPatPos[i], alignPatPos[j]);
}
}
// Draw configuration data
drawFormatBits(0); // Dummy mask value; overwritten later in the constructor
drawVersion();
}
// Draws two copies of the format bits (with its own error correction code)
// based on the given mask and this object's error correction level field.
private void drawFormatBits(int msk) {
@ -390,7 +390,7 @@ public final class QrCode {
rem = (rem << 1) ^ ((rem >>> 9) * 0x537);
int bits = (data << 10 | rem) ^ 0x5412; // uint15
assert bits >>> 15 == 0;
// Draw first copy
for (int i = 0; i <= 5; i++)
setFunctionModule(8, i, getBit(bits, i));
@ -399,7 +399,7 @@ public final class QrCode {
setFunctionModule(7, 8, getBit(bits, 8));
for (int i = 9; i < 15; i++)
setFunctionModule(14 - i, 8, getBit(bits, i));
// Draw second copy
for (int i = 0; i < 8; i++)
setFunctionModule(size - 1 - i, 8, getBit(bits, i));
@ -407,21 +407,21 @@ public final class QrCode {
setFunctionModule(8, size - 15 + i, getBit(bits, i));
setFunctionModule(8, size - 8, true); // Always black
}
// Draws two copies of the version bits (with its own error correction code),
// based on this object's version field, iff 7 <= version <= 40.
private void drawVersion() {
if (version < 7)
return;
// Calculate error correction code and pack bits
int rem = version; // version is uint6, in the range [7, 40]
for (int i = 0; i < 12; i++)
rem = (rem << 1) ^ ((rem >>> 11) * 0x1F25);
int bits = version << 12 | rem; // uint18
assert bits >>> 18 == 0;
// Draw two copies
for (int i = 0; i < 18; i++) {
boolean bit = getBit(bits, i);
@ -431,8 +431,8 @@ public final class QrCode {
setFunctionModule(b, a, bit);
}
}
// Draws a 9*9 finder pattern including the border separator,
// with the center module at (x, y). Modules can be out of bounds.
private void drawFinderPattern(int x, int y) {
@ -445,8 +445,8 @@ public final class QrCode {
}
}
}
// Draws a 5*5 alignment pattern, with the center module
// at (x, y). All modules must be in bounds.
private void drawAlignmentPattern(int x, int y) {
@ -455,32 +455,32 @@ public final class QrCode {
setFunctionModule(x + dx, y + dy, Math.max(Math.abs(dx), Math.abs(dy)) != 1);
}
}
// Sets the color of a module and marks it as a function module.
// Only used by the constructor. Coordinates must be in bounds.
private void setFunctionModule(int x, int y, boolean isBlack) {
modules[y][x] = isBlack;
isFunction[y][x] = true;
}
/*---- Private helper methods for constructor: Codewords and masking ----*/
// Returns a new byte string representing the given data with the appropriate error correction
// codewords appended to it, based on this object's version and error correction level.
private byte[] addEccAndInterleave(byte[] data) {
Objects.requireNonNull(data);
if (data.length != getNumDataCodewords(version, errorCorrectionLevel))
throw new IllegalArgumentException();
// Calculate parameter numbers
int numBlocks = NUM_ERROR_CORRECTION_BLOCKS[errorCorrectionLevel.ordinal()][version];
int blockEccLen = ECC_CODEWORDS_PER_BLOCK [errorCorrectionLevel.ordinal()][version];
int rawCodewords = getNumRawDataModules(version) / 8;
int numShortBlocks = numBlocks - rawCodewords % numBlocks;
int shortBlockLen = rawCodewords / numBlocks;
// Split data into blocks and append ECC to each block
byte[][] blocks = new byte[numBlocks][];
byte[] rsDiv = reedSolomonComputeDivisor(blockEccLen);
@ -492,7 +492,7 @@ public final class QrCode {
System.arraycopy(ecc, 0, block, block.length - blockEccLen, ecc.length);
blocks[i] = block;
}
// Interleave (not concatenate) the bytes from every block into a single sequence
byte[] result = new byte[rawCodewords];
for (int i = 0, k = 0; i < blocks[0].length; i++) {
@ -506,15 +506,15 @@ public final class QrCode {
}
return result;
}
// Draws the given sequence of 8-bit codewords (data and error correction) onto the entire
// data area of this QR Code. Function modules need to be marked off before this is called.
private void drawCodewords(byte[] data) {
Objects.requireNonNull(data);
if (data.length != getNumRawDataModules(version) / 8)
throw new IllegalArgumentException();
int i = 0; // Bit index into the data
// Do the funny zigzag scan
for (int right = size - 1; right >= 1; right -= 2) { // Index of right column in each column pair
@ -536,13 +536,13 @@ public final class QrCode {
}
assert i == data.length * 8;
}
// XORs the codeword modules in this QR Code with the given mask pattern.
// The function modules must be marked and the codeword bits must be drawn
// before masking. Due to the arithmetic of XOR, calling applyMask() with
// the same mask value a second time will undo the mask. A final well-formed
// QR Code needs exactly one (not zero, two, etc.) mask applied. switch-statement refactoring
// QR Code needs exactly one (not zero, two, etc.) mask applied. Command pattern
private void applyMask(int msk) {
if (msk < 0 || msk > 7)
throw new IllegalArgumentException("Mask value out of range");
@ -550,38 +550,28 @@ public final class QrCode {
for (int x = 0; x < size; x++) {
boolean invert;
switch (msk) {
case 0: invert = (x + y) % 2 == 0; break;
case 1: invert = y % 2 == 0; break;
case 2: invert = x % 3 == 0; break;
case 3: invert = (x + y) % 3 == 0; break;
case 4: invert = (x / 3 + y / 2) % 2 == 0; break;
case 5: invert = x * y % 2 + x * y % 3 == 0; break;
case 6: invert = (x * y % 2 + x * y % 3) % 2 == 0; break;
case 7: invert = ((x + y) % 2 + x * y % 3) % 2 == 0; break;
default: throw new AssertionError();
case 0: invert = (x + y) % 2 == 0; break;
case 1: invert = y % 2 == 0; break;
case 2: invert = x % 3 == 0; break;
case 3: invert = (x + y) % 3 == 0; break;
case 4: invert = (x / 3 + y / 2) % 2 == 0; break;
case 5: invert = x * y % 2 + x * y % 3 == 0; break;
case 6: invert = (x * y % 2 + x * y % 3) % 2 == 0; break;
case 7: invert = ((x + y) % 2 + x * y % 3) % 2 == 0; break;
default: throw new AssertionError();
}
modules[y][x] ^= invert & !isFunction[y][x];
}
}
}
// A messy helper function for the constructor. This QR Code must be in an unmasked state when this
// method is called. The given argument is the requested mask, which is -1 for auto or 0 to 7 for fixed.
// This method applies and returns the actual mask chosen, from 0 to 7.
private int handleConstructorMasking(int msk) {
if (msk == -1) { // Automatically choose best mask
int minPenalty = Integer.MAX_VALUE;
for (int i = 0; i < 8; i++) {
applyMask(i);
drawFormatBits(i);
int penalty = getPenaltyScore();
if (penalty < minPenalty) {
msk = i;
minPenalty = penalty;
}
applyMask(i); // Undoes the mask due to XOR
}
msk = chooseBestMask(msk);
}
assert 0 <= msk && msk <= 7;
applyMask(msk); // Apply the final choice of mask
@ -589,32 +579,67 @@ public final class QrCode {
return msk; // The caller shall assign this value to the final-declared field
}
private int chooseBestMask(int msk) {
int minPenalty = Integer.MAX_VALUE;
for (int i = 0; i < 8; i++) {
applyMask(i);
drawFormatBits(i);
int penalty = getPenaltyScore();
if (penalty < minPenalty) {
msk = i;
minPenalty = penalty;
}
applyMask(i); // Undoes the mask due to XOR
}
return msk;
}
private int havingSameColor(int run, boolean runColor, int[] runHistory, int result, int y, int x) {
if (modules[y][x] == runColor) {
run++;
if (run == 5)
result += PENALTY_N1;
else if (run > 5)
result++;
} else {
finderPenaltyAddHistory(run, runHistory);
if (!runColor)
result += finderPenaltyCountPatterns(runHistory) * PENALTY_N3;
runColor = modules[y][x];
run = 1;
}
return result;
}
private int twobytwoHavingSameColor(boolean[][] modules) {
int result = 0;
// 2*2 blocks of modules having same color.
for (int y = 0; y < size - 1; y++) {
for (int x = 0; x < size - 1; x++) {
boolean color = modules[y][x];
if ( color == modules[y][x + 1] &&
color == modules[y + 1][x] &&
color == modules[y + 1][x + 1])
result += PENALTY_N2;
}
}
return result;
}
// Calculates and returns the penalty score based on state of this QR Code's current modules.
// This is used by the automatic mask choice algorithm to find the mask pattern that yields the lowest score. duplication code extract
// This is used by the automatic mask choice algorithm to find the mask pattern that yields the lowest score.
private int getPenaltyScore() {
int result = 0;
int result = 0;
// Adjacent modules in row having same color, and finder-like patterns
for (int y = 0; y < size; y++) {
boolean runColor = false;
int runX = 0;
int[] runHistory = new int[7];
result += havingSameColor();
for (int x = 0; x < size; x++) {
if (modules[y][x] == runColor) {
runX++;
if (runX == 5)
result += PENALTY_N1;
else if (runX > 5)
result++;
} else {
finderPenaltyAddHistory(runX, runHistory);
if (!runColor)
result += finderPenaltyCountPatterns(runHistory) * PENALTY_N3;
runColor = modules[y][x];
runX = 1;
}
result += havingSameColor(runX, runColor, runHistory, result, y, x);
}
result += finderPenaltyTerminateAndCount(runColor, runX, runHistory) * PENALTY_N3;
}
@ -624,34 +649,14 @@ public final class QrCode {
int runY = 0;
int[] runHistory = new int[7];
for (int y = 0; y < size; y++) {
if (modules[y][x] == runColor) {
runY++;
if (runY == 5)
result += PENALTY_N1;
else if (runY > 5)
result++;
} else {
finderPenaltyAddHistory(runY, runHistory);
if (!runColor)
result += finderPenaltyCountPatterns(runHistory) * PENALTY_N3;
runColor = modules[y][x];
runY = 1;
}
result += havingSameColor(runY, runColor, runHistory, result, y, x);
}
result += finderPenaltyTerminateAndCount(runColor, runY, runHistory) * PENALTY_N3;
}
// 2*2 blocks of modules having same color. extract method to reduce method size
for (int y = 0; y < size - 1; y++) {
for (int x = 0; x < size - 1; x++) {
boolean color = modules[y][x];
if ( color == modules[y][x + 1] &&
color == modules[y + 1][x] &&
color == modules[y + 1][x + 1])
result += PENALTY_N2;
}
}
result += twobytwoHavingSameColor(modules);
// Balance of black and white modules
int black = 0;
for (boolean[] row : modules) {
@ -666,11 +671,9 @@ public final class QrCode {
result += k * PENALTY_N4;
return result;
}
/*---- Private helper functions ----*/
// Returns an ascending list of positions of alignment patterns for this version number.
// Each position is in the range [0,177), and are used on both the x and y axes.
// This could be implemented as lookup table of 40 variable-length lists of unsigned bytes.
@ -691,15 +694,22 @@ public final class QrCode {
return result;
}
}
// Returns the number of data bits that can be stored in a QR Code of the given version number, after
// all function modules are excluded. This includes remainder bits, so it might not be a multiple of 8.
// The result is in the range [208, 29648]. This could be implemented as a 40-entry lookup table. replace integer to understandable word
// The result is in the range [208, 29648]. This could be implemented as a 40-entry lookup table.
private static int getNumRawDataModules(int ver) {
if (ver < MIN_VERSION || ver > MAX_VERSION)
throw new IllegalArgumentException("Version number out of range");
int result = calculateNumOfModules(ver);
assert 208 <= result && result <= 29648;
return result;
}
private static int calculateNumOfModules(int ver) {
int size = ver * 4 + 17;
int result = size * size; // Number of modules in the whole QR Code square
result -= 8 * 8 * 3; // Subtract the three finders with separators
@ -714,11 +724,9 @@ public final class QrCode {
if (ver >= 7)
result -= 6 * 3 * 2; // Subtract version information
}
assert 208 <= result && result <= 29648;
return result;
}
// Returns a Reed-Solomon ECC generator polynomial for the given degree. This could be
// implemented as a lookup table over all possible parameter values, instead of as an algorithm.
private static byte[] reedSolomonComputeDivisor(int degree) {
@ -728,7 +736,7 @@ public final class QrCode {
// For example the polynomial x^3 + 255x^2 + 8x + 93 is stored as the uint8 array {255, 8, 93}.
byte[] result = new byte[degree];
result[degree - 1] = 1; // Start off with the monomial x^0
// Compute the product polynomial (x - r^0) * (x - r^1) * (x - r^2) * ... * (x - r^{degree-1}),
// and drop the highest monomial term which is always 1x^degree.
// Note that r = 0x02, which is a generator element of this field GF(2^8/0x11D).
@ -744,8 +752,8 @@ public final class QrCode {
}
return result;
}
// Returns the Reed-Solomon error correction codeword for the given data and divisor polynomials.
private static byte[] reedSolomonComputeRemainder(byte[] data, byte[] divisor) {
Objects.requireNonNull(data);
@ -760,33 +768,33 @@ public final class QrCode {
}
return result;
}
// Returns the product of the two given field elements modulo GF(2^8/0x11D). The arguments and result
// are unsigned 8-bit integers. This could be implemented as a lookup table of 256*256 entries of uint8.
private static int reedSolomonMultiply(int x, int y) {
assert x >> 8 == 0 && y >> 8 == 0;
// Russian peasant multiplication
int z = 0;
for (int i = 7; i >= 0; i--) {
z = (z << 1) ^ ((z >>> 7) * 0x11D);
z ^= ((y >>> i) & 1) * x;
}
assert z >>> 8 == 0;
return z;
// Russian peasant multiplication
int z = 0;
for (int i = 7; i >= 0; i--) {
z = (z << 1) ^ ((z >>> 7) * 0x11D);
z ^= ((y >>> i) & 1) * x;
}
assert z >>> 8 == 0;
return z;
}
// Returns the number of 8-bit data (i.e. not error correction) codewords contained in any
// QR Code of the given version number and error correction level, with remainder bits discarded.
// This stateless pure function could be implemented as a (40*4)-cell lookup table.
static int getNumDataCodewords(int ver, Ecc ecl) {
return getNumRawDataModules(ver) / 8
- ECC_CODEWORDS_PER_BLOCK [ecl.ordinal()][ver]
* NUM_ERROR_CORRECTION_BLOCKS[ecl.ordinal()][ver];
- ECC_CODEWORDS_PER_BLOCK [ecl.ordinal()][ver]
* NUM_ERROR_CORRECTION_BLOCKS[ecl.ordinal()][ver];
}
// Can only be called immediately after a white run is added, and
// returns either 0, 1, or 2. A helper function for getPenaltyScore().
private int finderPenaltyCountPatterns(int[] runHistory) {
@ -794,10 +802,10 @@ public final class QrCode {
assert n <= size * 3;
boolean core = n > 0 && runHistory[2] == n && runHistory[3] == n * 3 && runHistory[4] == n && runHistory[5] == n;
return (core && runHistory[0] >= n * 4 && runHistory[6] >= n ? 1 : 0)
+ (core && runHistory[6] >= n * 4 && runHistory[0] >= n ? 1 : 0);
+ (core && runHistory[6] >= n * 4 && runHistory[0] >= n ? 1 : 0);
}
// Must be called at the end of a line (row or column) of modules. A helper function for getPenaltyScore().
private int finderPenaltyTerminateAndCount(boolean currentRunColor, int currentRunLength, int[] runHistory) {
if (currentRunColor) { // Terminate black run
@ -808,8 +816,8 @@ public final class QrCode {
finderPenaltyAddHistory(currentRunLength, runHistory);
return finderPenaltyCountPatterns(runHistory);
}
// Pushes the given value to the front and drops the last value. A helper function for getPenaltyScore().
private void finderPenaltyAddHistory(int currentRunLength, int[] runHistory) {
if (runHistory[0] == 0)
@ -817,52 +825,52 @@ public final class QrCode {
System.arraycopy(runHistory, 0, runHistory, 1, runHistory.length - 1);
runHistory[0] = currentRunLength;
}
// Returns true iff the i'th bit of x is set to 1.
static boolean getBit(int x, int i) {
return ((x >>> i) & 1) != 0;
}
/*---- Constants and tables ----*/
/** The minimum version number (1) supported in the QR Code Model 2 standard. */
public static final int MIN_VERSION = 1;
/** The maximum version number (40) supported in the QR Code Model 2 standard. */
public static final int MAX_VERSION = 40;
// For use in getPenaltyScore(), when evaluating which mask is best.
private static final int PENALTY_N1 = 3;
private static final int PENALTY_N2 = 3;
private static final int PENALTY_N3 = 40;
private static final int PENALTY_N4 = 10;
private static final byte[][] ECC_CODEWORDS_PER_BLOCK = {
// Version: (note that index 0 is for padding, and is set to an illegal value)
//0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level
{-1, 7, 10, 15, 20, 26, 18, 20, 24, 30, 18, 20, 24, 26, 30, 22, 24, 28, 30, 28, 28, 28, 28, 30, 30, 26, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Low
{-1, 10, 16, 26, 18, 24, 16, 18, 22, 22, 26, 30, 22, 22, 24, 24, 28, 28, 26, 26, 26, 26, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28}, // Medium
{-1, 13, 22, 18, 26, 18, 24, 18, 22, 20, 24, 28, 26, 24, 20, 30, 24, 28, 28, 26, 30, 28, 30, 30, 30, 30, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Quartile
{-1, 17, 28, 22, 16, 22, 28, 26, 26, 24, 28, 24, 28, 22, 24, 24, 30, 28, 28, 26, 28, 30, 24, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // High
// Version: (note that index 0 is for padding, and is set to an illegal value)
//0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level
{-1, 7, 10, 15, 20, 26, 18, 20, 24, 30, 18, 20, 24, 26, 30, 22, 24, 28, 30, 28, 28, 28, 28, 30, 30, 26, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Low
{-1, 10, 16, 26, 18, 24, 16, 18, 22, 22, 26, 30, 22, 22, 24, 24, 28, 28, 26, 26, 26, 26, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28}, // Medium
{-1, 13, 22, 18, 26, 18, 24, 18, 22, 20, 24, 28, 26, 24, 20, 30, 24, 28, 28, 26, 30, 28, 30, 30, 30, 30, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // Quartile
{-1, 17, 28, 22, 16, 22, 28, 26, 26, 24, 28, 24, 28, 22, 24, 24, 30, 28, 28, 26, 28, 30, 24, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30}, // High
};
private static final byte[][] NUM_ERROR_CORRECTION_BLOCKS = {
// Version: (note that index 0 is for padding, and is set to an illegal value)
//0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level
{-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 4, 4, 6, 6, 6, 6, 7, 8, 8, 9, 9, 10, 12, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 24, 25}, // Low
{-1, 1, 1, 1, 2, 2, 4, 4, 4, 5, 5, 5, 8, 9, 9, 10, 10, 11, 13, 14, 16, 17, 17, 18, 20, 21, 23, 25, 26, 28, 29, 31, 33, 35, 37, 38, 40, 43, 45, 47, 49}, // Medium
{-1, 1, 1, 2, 2, 4, 4, 6, 6, 8, 8, 8, 10, 12, 16, 12, 17, 16, 18, 21, 20, 23, 23, 25, 27, 29, 34, 34, 35, 38, 40, 43, 45, 48, 51, 53, 56, 59, 62, 65, 68}, // Quartile
{-1, 1, 1, 2, 4, 4, 4, 5, 6, 8, 8, 11, 11, 16, 16, 18, 16, 19, 21, 25, 25, 25, 34, 30, 32, 35, 37, 40, 42, 45, 48, 51, 54, 57, 60, 63, 66, 70, 74, 77, 81}, // High
// Version: (note that index 0 is for padding, and is set to an illegal value)
//0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40 Error correction level
{-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 4, 4, 6, 6, 6, 6, 7, 8, 8, 9, 9, 10, 12, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 24, 25}, // Low
{-1, 1, 1, 1, 2, 2, 4, 4, 4, 5, 5, 5, 8, 9, 9, 10, 10, 11, 13, 14, 16, 17, 17, 18, 20, 21, 23, 25, 26, 28, 29, 31, 33, 35, 37, 38, 40, 43, 45, 47, 49}, // Medium
{-1, 1, 1, 2, 2, 4, 4, 6, 6, 8, 8, 8, 10, 12, 16, 12, 17, 16, 18, 21, 20, 23, 23, 25, 27, 29, 34, 34, 35, 38, 40, 43, 45, 48, 51, 53, 56, 59, 62, 65, 68}, // Quartile
{-1, 1, 1, 2, 4, 4, 4, 5, 6, 8, 8, 11, 11, 16, 16, 18, 16, 19, 21, 25, 25, 25, 34, 30, 32, 35, 37, 40, 42, 45, 48, 51, 54, 57, 60, 63, 66, 70, 74, 77, 81}, // High
};
/*---- Public helper enumeration ----*/
/**
* The error correction level in a QR Code symbol.
*/
@ -873,14 +881,14 @@ public final class QrCode {
/** The QR Code can tolerate about 15% erroneous codewords. */ MEDIUM(0),
/** The QR Code can tolerate about 25% erroneous codewords. */ QUARTILE(3),
/** The QR Code can tolerate about 30% erroneous codewords. */ HIGH(2);
// In the range 0 to 3 (unsigned 2-bit integer).
final int formatBits;
// Constructor.
private Ecc(int fb) {
formatBits = fb;
}
}
}

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