--- /dev/null
+/*
+ * QR Code generator library (C++)
+ *
+ * Copyright (c) Project Nayuki. (MIT License)
+ * https://www.nayuki.io/page/qr-code-generator-library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ * - The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * - The Software is provided "as is", without warranty of any kind, express or
+ * implied, including but not limited to the warranties of merchantability,
+ * fitness for a particular purpose and noninfringement. In no event shall the
+ * authors or copyright holders be liable for any claim, damages or other
+ * liability, whether in an action of contract, tort or otherwise, arising from,
+ * out of or in connection with the Software or the use or other dealings in the
+ * Software.
+ */
+
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <cstddef>
+#include <cstdlib>
+#include <cstring>
+#include <sstream>
+#include <utility>
+#include "qrcodegen.hpp"
+
+using std::int8_t;
+using std::uint8_t;
+using std::size_t;
+using std::vector;
+
+
+namespace qrcodegen {
+
+/*---- Class QrSegment ----*/
+
+QrSegment::Mode::Mode(int mode, int cc0, int cc1, int cc2) :
+ modeBits(mode) {
+ numBitsCharCount[0] = cc0;
+ numBitsCharCount[1] = cc1;
+ numBitsCharCount[2] = cc2;
+}
+
+
+int QrSegment::Mode::getModeBits() const {
+ return modeBits;
+}
+
+
+int QrSegment::Mode::numCharCountBits(int ver) const {
+ return numBitsCharCount[(ver + 7) / 17];
+}
+
+
+const QrSegment::Mode QrSegment::Mode::NUMERIC (0x1, 10, 12, 14);
+const QrSegment::Mode QrSegment::Mode::ALPHANUMERIC(0x2, 9, 11, 13);
+const QrSegment::Mode QrSegment::Mode::BYTE (0x4, 8, 16, 16);
+const QrSegment::Mode QrSegment::Mode::KANJI (0x8, 8, 10, 12);
+const QrSegment::Mode QrSegment::Mode::ECI (0x7, 0, 0, 0);
+
+
+QrSegment QrSegment::makeBytes(const vector<uint8_t> &data) {
+ if (data.size() > static_cast<unsigned int>(INT_MAX))
+ throw std::length_error("Data too long");
+ BitBuffer bb;
+ for (uint8_t b : data)
+ bb.appendBits(b, 8);
+ return QrSegment(Mode::BYTE, static_cast<int>(data.size()), std::move(bb));
+}
+
+
+QrSegment QrSegment::makeNumeric(const char *digits) {
+ BitBuffer bb;
+ int accumData = 0;
+ int accumCount = 0;
+ int charCount = 0;
+ for (; *digits != '\0'; digits++, charCount++) {
+ char c = *digits;
+ if (c < '0' || c > '9')
+ throw std::domain_error("String contains non-numeric characters");
+ accumData = accumData * 10 + (c - '0');
+ accumCount++;
+ if (accumCount == 3) {
+ bb.appendBits(static_cast<uint32_t>(accumData), 10);
+ accumData = 0;
+ accumCount = 0;
+ }
+ }
+ if (accumCount > 0) // 1 or 2 digits remaining
+ bb.appendBits(static_cast<uint32_t>(accumData), accumCount * 3 + 1);
+ return QrSegment(Mode::NUMERIC, charCount, std::move(bb));
+}
+
+
+QrSegment QrSegment::makeAlphanumeric(const char *text) {
+ BitBuffer bb;
+ int accumData = 0;
+ int accumCount = 0;
+ int charCount = 0;
+ for (; *text != '\0'; text++, charCount++) {
+ const char *temp = std::strchr(ALPHANUMERIC_CHARSET, *text);
+ if (temp == nullptr)
+ throw std::domain_error("String contains unencodable characters in alphanumeric mode");
+ accumData = accumData * 45 + static_cast<int>(temp - ALPHANUMERIC_CHARSET);
+ accumCount++;
+ if (accumCount == 2) {
+ bb.appendBits(static_cast<uint32_t>(accumData), 11);
+ accumData = 0;
+ accumCount = 0;
+ }
+ }
+ if (accumCount > 0) // 1 character remaining
+ bb.appendBits(static_cast<uint32_t>(accumData), 6);
+ return QrSegment(Mode::ALPHANUMERIC, charCount, std::move(bb));
+}
+
+
+vector<QrSegment> QrSegment::makeSegments(const char *text) {
+ // Select the most efficient segment encoding automatically
+ vector<QrSegment> result;
+ if (*text == '\0'); // Leave result empty
+ else if (isNumeric(text))
+ result.push_back(makeNumeric(text));
+ else if (isAlphanumeric(text))
+ result.push_back(makeAlphanumeric(text));
+ else {
+ vector<uint8_t> bytes;
+ for (; *text != '\0'; text++)
+ bytes.push_back(static_cast<uint8_t>(*text));
+ result.push_back(makeBytes(bytes));
+ }
+ return result;
+}
+
+
+QrSegment QrSegment::makeEci(long assignVal) {
+ BitBuffer bb;
+ if (assignVal < 0)
+ throw std::domain_error("ECI assignment value out of range");
+ else if (assignVal < (1 << 7))
+ bb.appendBits(static_cast<uint32_t>(assignVal), 8);
+ else if (assignVal < (1 << 14)) {
+ bb.appendBits(2, 2);
+ bb.appendBits(static_cast<uint32_t>(assignVal), 14);
+ } else if (assignVal < 1000000L) {
+ bb.appendBits(6, 3);
+ bb.appendBits(static_cast<uint32_t>(assignVal), 21);
+ } else
+ throw std::domain_error("ECI assignment value out of range");
+ return QrSegment(Mode::ECI, 0, std::move(bb));
+}
+
+
+QrSegment::QrSegment(const Mode &md, int numCh, const std::vector<bool> &dt) :
+ mode(&md),
+ numChars(numCh),
+ data(dt) {
+ if (numCh < 0)
+ throw std::domain_error("Invalid value");
+}
+
+
+QrSegment::QrSegment(const Mode &md, int numCh, std::vector<bool> &&dt) :
+ mode(&md),
+ numChars(numCh),
+ data(std::move(dt)) {
+ if (numCh < 0)
+ throw std::domain_error("Invalid value");
+}
+
+
+int QrSegment::getTotalBits(const vector<QrSegment> &segs, int version) {
+ int result = 0;
+ for (const QrSegment &seg : segs) {
+ int ccbits = seg.mode->numCharCountBits(version);
+ if (seg.numChars >= (1L << ccbits))
+ return -1; // The segment's length doesn't fit the field's bit width
+ if (4 + ccbits > INT_MAX - result)
+ return -1; // The sum will overflow an int type
+ result += 4 + ccbits;
+ if (seg.data.size() > static_cast<unsigned int>(INT_MAX - result))
+ return -1; // The sum will overflow an int type
+ result += static_cast<int>(seg.data.size());
+ }
+ return result;
+}
+
+
+bool QrSegment::isNumeric(const char *text) {
+ for (; *text != '\0'; text++) {
+ char c = *text;
+ if (c < '0' || c > '9')
+ return false;
+ }
+ return true;
+}
+
+
+bool QrSegment::isAlphanumeric(const char *text) {
+ for (; *text != '\0'; text++) {
+ if (std::strchr(ALPHANUMERIC_CHARSET, *text) == nullptr)
+ return false;
+ }
+ return true;
+}
+
+
+const QrSegment::Mode &QrSegment::getMode() const {
+ return *mode;
+}
+
+
+int QrSegment::getNumChars() const {
+ return numChars;
+}
+
+
+const std::vector<bool> &QrSegment::getData() const {
+ return data;
+}
+
+
+const char *QrSegment::ALPHANUMERIC_CHARSET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:";
+
+
+
+/*---- Class QrCode ----*/
+
+int QrCode::getFormatBits(Ecc ecl) {
+ switch (ecl) {
+ case Ecc::LOW : return 1;
+ case Ecc::MEDIUM : return 0;
+ case Ecc::QUARTILE: return 3;
+ case Ecc::HIGH : return 2;
+ default: throw std::logic_error("Unreachable");
+ }
+}
+
+
+QrCode QrCode::encodeText(const char *text, Ecc ecl) {
+ vector<QrSegment> segs = QrSegment::makeSegments(text);
+ return encodeSegments(segs, ecl);
+}
+
+
+QrCode QrCode::encodeBinary(const vector<uint8_t> &data, Ecc ecl) {
+ vector<QrSegment> segs{QrSegment::makeBytes(data)};
+ return encodeSegments(segs, ecl);
+}
+
+
+QrCode QrCode::encodeSegments(const vector<QrSegment> &segs, Ecc ecl,
+ int minVersion, int maxVersion, int mask, bool boostEcl) {
+ if (!(MIN_VERSION <= minVersion && minVersion <= maxVersion && maxVersion <= MAX_VERSION) || mask < -1 || mask > 7)
+ throw std::invalid_argument("Invalid value");
+
+ // Find the minimal version number to use
+ int version, dataUsedBits;
+ for (version = minVersion; ; version++) {
+ int dataCapacityBits = getNumDataCodewords(version, ecl) * 8; // Number of data bits available
+ dataUsedBits = QrSegment::getTotalBits(segs, version);
+ if (dataUsedBits != -1 && dataUsedBits <= dataCapacityBits)
+ break; // This version number is found to be suitable
+ if (version >= maxVersion) { // All versions in the range could not fit the given data
+ std::ostringstream sb;
+ if (dataUsedBits == -1)
+ sb << "Segment too long";
+ else {
+ sb << "Data length = " << dataUsedBits << " bits, ";
+ sb << "Max capacity = " << dataCapacityBits << " bits";
+ }
+ throw data_too_long(sb.str());
+ }
+ }
+ assert(dataUsedBits != -1);
+
+ // Increase the error correction level while the data still fits in the current version number
+ for (Ecc newEcl : {Ecc::MEDIUM, Ecc::QUARTILE, Ecc::HIGH}) { // From low to high
+ if (boostEcl && dataUsedBits <= getNumDataCodewords(version, newEcl) * 8)
+ ecl = newEcl;
+ }
+
+ // Concatenate all segments to create the data bit string
+ BitBuffer bb;
+ for (const QrSegment &seg : segs) {
+ bb.appendBits(static_cast<uint32_t>(seg.getMode().getModeBits()), 4);
+ bb.appendBits(static_cast<uint32_t>(seg.getNumChars()), seg.getMode().numCharCountBits(version));
+ bb.insert(bb.end(), seg.getData().begin(), seg.getData().end());
+ }
+ assert(bb.size() == static_cast<unsigned int>(dataUsedBits));
+
+ // Add terminator and pad up to a byte if applicable
+ size_t dataCapacityBits = static_cast<size_t>(getNumDataCodewords(version, ecl)) * 8;
+ assert(bb.size() <= dataCapacityBits);
+ bb.appendBits(0, std::min(4, static_cast<int>(dataCapacityBits - bb.size())));
+ bb.appendBits(0, (8 - static_cast<int>(bb.size() % 8)) % 8);
+ assert(bb.size() % 8 == 0);
+
+ // Pad with alternating bytes until data capacity is reached
+ for (uint8_t padByte = 0xEC; bb.size() < dataCapacityBits; padByte ^= 0xEC ^ 0x11)
+ bb.appendBits(padByte, 8);
+
+ // Pack bits into bytes in big endian
+ vector<uint8_t> dataCodewords(bb.size() / 8);
+ for (size_t i = 0; i < bb.size(); i++)
+ dataCodewords.at(i >> 3) |= (bb.at(i) ? 1 : 0) << (7 - (i & 7));
+
+ // Create the QR Code object
+ return QrCode(version, ecl, dataCodewords, mask);
+}
+
+
+QrCode::QrCode(int ver, Ecc ecl, const vector<uint8_t> &dataCodewords, int msk) :
+ // Initialize fields and check arguments
+ version(ver),
+ errorCorrectionLevel(ecl) {
+ if (ver < MIN_VERSION || ver > MAX_VERSION)
+ throw std::domain_error("Version value out of range");
+ if (msk < -1 || msk > 7)
+ throw std::domain_error("Mask value out of range");
+ size = ver * 4 + 17;
+ size_t sz = static_cast<size_t>(size);
+ modules = vector<vector<bool> >(sz, vector<bool>(sz)); // Initially all light
+ isFunction = vector<vector<bool> >(sz, vector<bool>(sz));
+
+ // Compute ECC, draw modules
+ drawFunctionPatterns();
+ const vector<uint8_t> allCodewords = addEccAndInterleave(dataCodewords);
+ drawCodewords(allCodewords);
+
+ // Do masking
+ if (msk == -1) { // Automatically choose best mask
+ long minPenalty = LONG_MAX;
+ for (int i = 0; i < 8; i++) {
+ applyMask(i);
+ drawFormatBits(i);
+ long penalty = getPenaltyScore();
+ if (penalty < minPenalty) {
+ msk = i;
+ minPenalty = penalty;
+ }
+ applyMask(i); // Undoes the mask due to XOR
+ }
+ }
+ assert(0 <= msk && msk <= 7);
+ mask = msk;
+ applyMask(msk); // Apply the final choice of mask
+ drawFormatBits(msk); // Overwrite old format bits
+
+ isFunction.clear();
+ isFunction.shrink_to_fit();
+}
+
+
+int QrCode::getVersion() const {
+ return version;
+}
+
+
+int QrCode::getSize() const {
+ return size;
+}
+
+
+QrCode::Ecc QrCode::getErrorCorrectionLevel() const {
+ return errorCorrectionLevel;
+}
+
+
+int QrCode::getMask() const {
+ return mask;
+}
+
+
+bool QrCode::getModule(int x, int y) const {
+ return 0 <= x && x < size && 0 <= y && y < size && module(x, y);
+}
+
+
+void QrCode::drawFunctionPatterns() {
+ // Draw horizontal and vertical timing patterns
+ for (int i = 0; i < size; i++) {
+ 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
+ const vector<int> alignPatPos = getAlignmentPatternPositions();
+ size_t numAlign = alignPatPos.size();
+ for (size_t i = 0; i < numAlign; i++) {
+ for (size_t j = 0; j < numAlign; j++) {
+ // Don't draw on the three finder corners
+ if (!((i == 0 && j == 0) || (i == 0 && j == numAlign - 1) || (i == numAlign - 1 && j == 0)))
+ drawAlignmentPattern(alignPatPos.at(i), alignPatPos.at(j));
+ }
+ }
+
+ // Draw configuration data
+ drawFormatBits(0); // Dummy mask value; overwritten later in the constructor
+ drawVersion();
+}
+
+
+void QrCode::drawFormatBits(int msk) {
+ // Calculate error correction code and pack bits
+ int data = getFormatBits(errorCorrectionLevel) << 3 | msk; // errCorrLvl is uint2, msk is uint3
+ int rem = data;
+ for (int i = 0; i < 10; i++)
+ 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));
+ setFunctionModule(8, 7, getBit(bits, 6));
+ setFunctionModule(8, 8, getBit(bits, 7));
+ 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));
+ for (int i = 8; i < 15; i++)
+ setFunctionModule(8, size - 15 + i, getBit(bits, i));
+ setFunctionModule(8, size - 8, true); // Always dark
+}
+
+
+void QrCode::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);
+ long bits = static_cast<long>(version) << 12 | rem; // uint18
+ assert(bits >> 18 == 0);
+
+ // Draw two copies
+ for (int i = 0; i < 18; i++) {
+ bool bit = getBit(bits, i);
+ int a = size - 11 + i % 3;
+ int b = i / 3;
+ setFunctionModule(a, b, bit);
+ setFunctionModule(b, a, bit);
+ }
+}
+
+
+void QrCode::drawFinderPattern(int x, int y) {
+ for (int dy = -4; dy <= 4; dy++) {
+ for (int dx = -4; dx <= 4; dx++) {
+ int dist = std::max(std::abs(dx), std::abs(dy)); // Chebyshev/infinity norm
+ int xx = x + dx, yy = y + dy;
+ if (0 <= xx && xx < size && 0 <= yy && yy < size)
+ setFunctionModule(xx, yy, dist != 2 && dist != 4);
+ }
+ }
+}
+
+
+void QrCode::drawAlignmentPattern(int x, int y) {
+ for (int dy = -2; dy <= 2; dy++) {
+ for (int dx = -2; dx <= 2; dx++)
+ setFunctionModule(x + dx, y + dy, std::max(std::abs(dx), std::abs(dy)) != 1);
+ }
+}
+
+
+void QrCode::setFunctionModule(int x, int y, bool isDark) {
+ size_t ux = static_cast<size_t>(x);
+ size_t uy = static_cast<size_t>(y);
+ modules .at(uy).at(ux) = isDark;
+ isFunction.at(uy).at(ux) = true;
+}
+
+
+bool QrCode::module(int x, int y) const {
+ return modules.at(static_cast<size_t>(y)).at(static_cast<size_t>(x));
+}
+
+
+vector<uint8_t> QrCode::addEccAndInterleave(const vector<uint8_t> &data) const {
+ if (data.size() != static_cast<unsigned int>(getNumDataCodewords(version, errorCorrectionLevel)))
+ throw std::invalid_argument("Invalid argument");
+
+ // Calculate parameter numbers
+ int numBlocks = NUM_ERROR_CORRECTION_BLOCKS[static_cast<int>(errorCorrectionLevel)][version];
+ int blockEccLen = ECC_CODEWORDS_PER_BLOCK [static_cast<int>(errorCorrectionLevel)][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
+ vector<vector<uint8_t> > blocks;
+ const vector<uint8_t> rsDiv = reedSolomonComputeDivisor(blockEccLen);
+ for (int i = 0, k = 0; i < numBlocks; i++) {
+ vector<uint8_t> dat(data.cbegin() + k, data.cbegin() + (k + shortBlockLen - blockEccLen + (i < numShortBlocks ? 0 : 1)));
+ k += static_cast<int>(dat.size());
+ const vector<uint8_t> ecc = reedSolomonComputeRemainder(dat, rsDiv);
+ if (i < numShortBlocks)
+ dat.push_back(0);
+ dat.insert(dat.end(), ecc.cbegin(), ecc.cend());
+ blocks.push_back(std::move(dat));
+ }
+
+ // Interleave (not concatenate) the bytes from every block into a single sequence
+ vector<uint8_t> result;
+ for (size_t i = 0; i < blocks.at(0).size(); i++) {
+ for (size_t j = 0; j < blocks.size(); j++) {
+ // Skip the padding byte in short blocks
+ if (i != static_cast<unsigned int>(shortBlockLen - blockEccLen) || j >= static_cast<unsigned int>(numShortBlocks))
+ result.push_back(blocks.at(j).at(i));
+ }
+ }
+ assert(result.size() == static_cast<unsigned int>(rawCodewords));
+ return result;
+}
+
+
+void QrCode::drawCodewords(const vector<uint8_t> &data) {
+ if (data.size() != static_cast<unsigned int>(getNumRawDataModules(version) / 8))
+ throw std::invalid_argument("Invalid argument");
+
+ size_t 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
+ if (right == 6)
+ right = 5;
+ for (int vert = 0; vert < size; vert++) { // Vertical counter
+ for (int j = 0; j < 2; j++) {
+ size_t x = static_cast<size_t>(right - j); // Actual x coordinate
+ bool upward = ((right + 1) & 2) == 0;
+ size_t y = static_cast<size_t>(upward ? size - 1 - vert : vert); // Actual y coordinate
+ if (!isFunction.at(y).at(x) && i < data.size() * 8) {
+ modules.at(y).at(x) = getBit(data.at(i >> 3), 7 - static_cast<int>(i & 7));
+ i++;
+ }
+ // If this QR Code has any remainder bits (0 to 7), they were assigned as
+ // 0/false/light by the constructor and are left unchanged by this method
+ }
+ }
+ }
+ assert(i == data.size() * 8);
+}
+
+
+void QrCode::applyMask(int msk) {
+ if (msk < 0 || msk > 7)
+ throw std::domain_error("Mask value out of range");
+ size_t sz = static_cast<size_t>(size);
+ for (size_t y = 0; y < sz; y++) {
+ for (size_t x = 0; x < sz; x++) {
+ bool 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 std::logic_error("Unreachable");
+ }
+ modules.at(y).at(x) = modules.at(y).at(x) ^ (invert & !isFunction.at(y).at(x));
+ }
+ }
+}
+
+
+long QrCode::getPenaltyScore() const {
+ long result = 0;
+
+ // Adjacent modules in row having same color, and finder-like patterns
+ for (int y = 0; y < size; y++) {
+ bool runColor = false;
+ int runX = 0;
+ std::array<int,7> runHistory = {};
+ for (int x = 0; x < size; x++) {
+ if (module(x, y) == 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 = module(x, y);
+ runX = 1;
+ }
+ }
+ result += finderPenaltyTerminateAndCount(runColor, runX, runHistory) * PENALTY_N3;
+ }
+ // Adjacent modules in column having same color, and finder-like patterns
+ for (int x = 0; x < size; x++) {
+ bool runColor = false;
+ int runY = 0;
+ std::array<int,7> runHistory = {};
+ for (int y = 0; y < size; y++) {
+ if (module(x, y) == 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 = module(x, y);
+ runY = 1;
+ }
+ }
+ result += finderPenaltyTerminateAndCount(runColor, runY, runHistory) * PENALTY_N3;
+ }
+
+ // 2*2 blocks of modules having same color
+ for (int y = 0; y < size - 1; y++) {
+ for (int x = 0; x < size - 1; x++) {
+ bool color = module(x, y);
+ if ( color == module(x + 1, y) &&
+ color == module(x, y + 1) &&
+ color == module(x + 1, y + 1))
+ result += PENALTY_N2;
+ }
+ }
+
+ // Balance of dark and light modules
+ int dark = 0;
+ for (const vector<bool> &row : modules) {
+ for (bool color : row) {
+ if (color)
+ dark++;
+ }
+ }
+ int total = size * size; // Note that size is odd, so dark/total != 1/2
+ // Compute the smallest integer k >= 0 such that (45-5k)% <= dark/total <= (55+5k)%
+ int k = static_cast<int>((std::abs(dark * 20L - total * 10L) + total - 1) / total) - 1;
+ assert(0 <= k && k <= 9);
+ result += k * PENALTY_N4;
+ assert(0 <= result && result <= 2568888L); // Non-tight upper bound based on default values of PENALTY_N1, ..., N4
+ return result;
+}
+
+
+vector<int> QrCode::getAlignmentPatternPositions() const {
+ if (version == 1)
+ return vector<int>();
+ else {
+ int numAlign = version / 7 + 2;
+ int step = (version * 8 + numAlign * 3 + 5) / (numAlign * 4 - 4) * 2;
+ vector<int> result;
+ for (int i = 0, pos = size - 7; i < numAlign - 1; i++, pos -= step)
+ result.insert(result.begin(), pos);
+ result.insert(result.begin(), 6);
+ return result;
+ }
+}
+
+
+int QrCode::getNumRawDataModules(int ver) {
+ if (ver < MIN_VERSION || ver > MAX_VERSION)
+ throw std::domain_error("Version number out of range");
+ int result = (16 * ver + 128) * ver + 64;
+ if (ver >= 2) {
+ int numAlign = ver / 7 + 2;
+ result -= (25 * numAlign - 10) * numAlign - 55;
+ if (ver >= 7)
+ result -= 36;
+ }
+ assert(208 <= result && result <= 29648);
+ return result;
+}
+
+
+int QrCode::getNumDataCodewords(int ver, Ecc ecl) {
+ return getNumRawDataModules(ver) / 8
+ - ECC_CODEWORDS_PER_BLOCK [static_cast<int>(ecl)][ver]
+ * NUM_ERROR_CORRECTION_BLOCKS[static_cast<int>(ecl)][ver];
+}
+
+
+vector<uint8_t> QrCode::reedSolomonComputeDivisor(int degree) {
+ if (degree < 1 || degree > 255)
+ throw std::domain_error("Degree out of range");
+ // Polynomial coefficients are stored from highest to lowest power, excluding the leading term which is always 1.
+ // For example the polynomial x^3 + 255x^2 + 8x + 93 is stored as the uint8 array {255, 8, 93}.
+ vector<uint8_t> result(static_cast<size_t>(degree));
+ result.at(result.size() - 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).
+ uint8_t root = 1;
+ for (int i = 0; i < degree; i++) {
+ // Multiply the current product by (x - r^i)
+ for (size_t j = 0; j < result.size(); j++) {
+ result.at(j) = reedSolomonMultiply(result.at(j), root);
+ if (j + 1 < result.size())
+ result.at(j) ^= result.at(j + 1);
+ }
+ root = reedSolomonMultiply(root, 0x02);
+ }
+ return result;
+}
+
+
+vector<uint8_t> QrCode::reedSolomonComputeRemainder(const vector<uint8_t> &data, const vector<uint8_t> &divisor) {
+ vector<uint8_t> result(divisor.size());
+ for (uint8_t b : data) { // Polynomial division
+ uint8_t factor = b ^ result.at(0);
+ result.erase(result.begin());
+ result.push_back(0);
+ for (size_t i = 0; i < result.size(); i++)
+ result.at(i) ^= reedSolomonMultiply(divisor.at(i), factor);
+ }
+ return result;
+}
+
+
+uint8_t QrCode::reedSolomonMultiply(uint8_t x, uint8_t y) {
+ // 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 static_cast<uint8_t>(z);
+}
+
+
+int QrCode::finderPenaltyCountPatterns(const std::array<int,7> &runHistory) const {
+ int n = runHistory.at(1);
+ assert(n <= size * 3);
+ bool core = n > 0 && runHistory.at(2) == n && runHistory.at(3) == n * 3 && runHistory.at(4) == n && runHistory.at(5) == n;
+ return (core && runHistory.at(0) >= n * 4 && runHistory.at(6) >= n ? 1 : 0)
+ + (core && runHistory.at(6) >= n * 4 && runHistory.at(0) >= n ? 1 : 0);
+}
+
+
+int QrCode::finderPenaltyTerminateAndCount(bool currentRunColor, int currentRunLength, std::array<int,7> &runHistory) const {
+ if (currentRunColor) { // Terminate dark run
+ finderPenaltyAddHistory(currentRunLength, runHistory);
+ currentRunLength = 0;
+ }
+ currentRunLength += size; // Add light border to final run
+ finderPenaltyAddHistory(currentRunLength, runHistory);
+ return finderPenaltyCountPatterns(runHistory);
+}
+
+
+void QrCode::finderPenaltyAddHistory(int currentRunLength, std::array<int,7> &runHistory) const {
+ if (runHistory.at(0) == 0)
+ currentRunLength += size; // Add light border to initial run
+ std::copy_backward(runHistory.cbegin(), runHistory.cend() - 1, runHistory.end());
+ runHistory.at(0) = currentRunLength;
+}
+
+
+bool QrCode::getBit(long x, int i) {
+ return ((x >> i) & 1) != 0;
+}
+
+
+/*---- Tables of constants ----*/
+
+const int QrCode::PENALTY_N1 = 3;
+const int QrCode::PENALTY_N2 = 3;
+const int QrCode::PENALTY_N3 = 40;
+const int QrCode::PENALTY_N4 = 10;
+
+
+const int8_t QrCode::ECC_CODEWORDS_PER_BLOCK[4][41] = {
+ // 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
+};
+
+const int8_t QrCode::NUM_ERROR_CORRECTION_BLOCKS[4][41] = {
+ // 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
+};
+
+
+data_too_long::data_too_long(const std::string &msg) :
+ std::length_error(msg) {}
+
+
+
+/*---- Class BitBuffer ----*/
+
+BitBuffer::BitBuffer()
+ : std::vector<bool>() {}
+
+
+void BitBuffer::appendBits(std::uint32_t val, int len) {
+ if (len < 0 || len > 31 || val >> len != 0)
+ throw std::domain_error("Value out of range");
+ for (int i = len - 1; i >= 0; i--) // Append bit by bit
+ this->push_back(((val >> i) & 1) != 0);
+}
+
+}
--- /dev/null
+/*
+ * QR Code generator library (C++)
+ *
+ * Copyright (c) Project Nayuki. (MIT License)
+ * https://www.nayuki.io/page/qr-code-generator-library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ * - The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * - The Software is provided "as is", without warranty of any kind, express or
+ * implied, including but not limited to the warranties of merchantability,
+ * fitness for a particular purpose and noninfringement. In no event shall the
+ * authors or copyright holders be liable for any claim, damages or other
+ * liability, whether in an action of contract, tort or otherwise, arising from,
+ * out of or in connection with the Software or the use or other dealings in the
+ * Software.
+ */
+
+#pragma once
+
+#include <array>
+#include <cstdint>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+
+namespace qrcodegen {
+
+/*
+ * A segment of character/binary/control data in a QR Code symbol.
+ * Instances of this class are immutable.
+ * The mid-level way to create a segment is to take the payload data
+ * and call a static factory function such as QrSegment::makeNumeric().
+ * The low-level way to create a segment is to custom-make the bit buffer
+ * and call the QrSegment() constructor with appropriate values.
+ * This segment class imposes no length restrictions, but QR Codes have restrictions.
+ * Even in the most favorable conditions, a QR Code can only hold 7089 characters of data.
+ * Any segment longer than this is meaningless for the purpose of generating QR Codes.
+ */
+class QrSegment final {
+
+ /*---- Public helper enumeration ----*/
+
+ /*
+ * Describes how a segment's data bits are interpreted. Immutable.
+ */
+ public: class Mode final {
+
+ /*-- Constants --*/
+
+ public: static const Mode NUMERIC;
+ public: static const Mode ALPHANUMERIC;
+ public: static const Mode BYTE;
+ public: static const Mode KANJI;
+ public: static const Mode ECI;
+
+
+ /*-- Fields --*/
+
+ // The mode indicator bits, which is a uint4 value (range 0 to 15).
+ private: int modeBits;
+
+ // Number of character count bits for three different version ranges.
+ private: int numBitsCharCount[3];
+
+
+ /*-- Constructor --*/
+
+ private: Mode(int mode, int cc0, int cc1, int cc2);
+
+
+ /*-- Methods --*/
+
+ /*
+ * (Package-private) Returns the mode indicator bits, which is an unsigned 4-bit value (range 0 to 15).
+ */
+ public: int getModeBits() const;
+
+ /*
+ * (Package-private) Returns the bit width of the character count field for a segment in
+ * this mode in a QR Code at the given version number. The result is in the range [0, 16].
+ */
+ public: int numCharCountBits(int ver) const;
+
+ };
+
+
+
+ /*---- Static factory functions (mid level) ----*/
+
+ /*
+ * Returns a segment representing the given binary data encoded in
+ * byte mode. All input byte vectors are acceptable. Any text string
+ * can be converted to UTF-8 bytes and encoded as a byte mode segment.
+ */
+ public: static QrSegment makeBytes(const std::vector<std::uint8_t> &data);
+
+
+ /*
+ * Returns a segment representing the given string of decimal digits encoded in numeric mode.
+ */
+ public: static QrSegment makeNumeric(const char *digits);
+
+
+ /*
+ * Returns a segment representing the given text string encoded in alphanumeric mode.
+ * The characters allowed are: 0 to 9, A to Z (uppercase only), space,
+ * dollar, percent, asterisk, plus, hyphen, period, slash, colon.
+ */
+ public: static QrSegment makeAlphanumeric(const char *text);
+
+
+ /*
+ * Returns a list of zero or more segments to represent the given text string. The result
+ * may use various segment modes and switch modes to optimize the length of the bit stream.
+ */
+ public: static std::vector<QrSegment> makeSegments(const char *text);
+
+
+ /*
+ * Returns a segment representing an Extended Channel Interpretation
+ * (ECI) designator with the given assignment value.
+ */
+ public: static QrSegment makeEci(long assignVal);
+
+
+ /*---- Public static helper functions ----*/
+
+ /*
+ * Tests whether the given string can be encoded as a segment in numeric mode.
+ * A string is encodable iff each character is in the range 0 to 9.
+ */
+ public: static bool isNumeric(const char *text);
+
+
+ /*
+ * Tests whether the given string can be encoded as a segment in alphanumeric mode.
+ * A string is encodable iff each character is in the following set: 0 to 9, A to Z
+ * (uppercase only), space, dollar, percent, asterisk, plus, hyphen, period, slash, colon.
+ */
+ public: static bool isAlphanumeric(const char *text);
+
+
+
+ /*---- Instance fields ----*/
+
+ /* The mode indicator of this segment. Accessed through getMode(). */
+ private: const Mode *mode;
+
+ /* The length of this segment's unencoded data. Measured in characters for
+ * numeric/alphanumeric/kanji mode, bytes for byte mode, and 0 for ECI mode.
+ * Always zero or positive. Not the same as the data's bit length.
+ * Accessed through getNumChars(). */
+ private: int numChars;
+
+ /* The data bits of this segment. Accessed through getData(). */
+ private: std::vector<bool> data;
+
+
+ /*---- Constructors (low level) ----*/
+
+ /*
+ * Creates a new QR Code segment with the given attributes and data.
+ * The character count (numCh) must agree with the mode and the bit buffer length,
+ * but the constraint isn't checked. The given bit buffer is copied and stored.
+ */
+ public: QrSegment(const Mode &md, int numCh, const std::vector<bool> &dt);
+
+
+ /*
+ * Creates a new QR Code segment with the given parameters and data.
+ * The character count (numCh) must agree with the mode and the bit buffer length,
+ * but the constraint isn't checked. The given bit buffer is moved and stored.
+ */
+ public: QrSegment(const Mode &md, int numCh, std::vector<bool> &&dt);
+
+
+ /*---- Methods ----*/
+
+ /*
+ * Returns the mode field of this segment.
+ */
+ public: const Mode &getMode() const;
+
+
+ /*
+ * Returns the character count field of this segment.
+ */
+ public: int getNumChars() const;
+
+
+ /*
+ * Returns the data bits of this segment.
+ */
+ public: const std::vector<bool> &getData() const;
+
+
+ // (Package-private) Calculates the number of bits needed to encode the given segments at
+ // the given version. Returns a non-negative number if successful. Otherwise returns -1 if a
+ // segment has too many characters to fit its length field, or the total bits exceeds INT_MAX.
+ public: static int getTotalBits(const std::vector<QrSegment> &segs, int version);
+
+
+ /*---- Private constant ----*/
+
+ /* The set of all legal characters in alphanumeric mode, where
+ * each character value maps to the index in the string. */
+ private: static const char *ALPHANUMERIC_CHARSET;
+
+};
+
+
+
+/*
+ * A QR Code symbol, which is a type of two-dimension barcode.
+ * Invented by Denso Wave and described in the ISO/IEC 18004 standard.
+ * Instances of this class represent an immutable square grid of dark and light cells.
+ * The class provides static factory functions to create a QR Code from text or binary data.
+ * The class covers the QR Code Model 2 specification, supporting all versions (sizes)
+ * from 1 to 40, all 4 error correction levels, and 4 character encoding modes.
+ *
+ * Ways to create a QR Code object:
+ * - High level: Take the payload data and call QrCode::encodeText() or QrCode::encodeBinary().
+ * - Mid level: Custom-make the list of segments and call QrCode::encodeSegments().
+ * - Low level: Custom-make the array of data codeword bytes (including
+ * segment headers and final padding, excluding error correction codewords),
+ * supply the appropriate version number, and call the QrCode() constructor.
+ * (Note that all ways require supplying the desired error correction level.)
+ */
+class QrCode final {
+
+ /*---- Public helper enumeration ----*/
+
+ /*
+ * The error correction level in a QR Code symbol.
+ */
+ public: enum class Ecc {
+ LOW = 0 , // The QR Code can tolerate about 7% erroneous codewords
+ MEDIUM , // The QR Code can tolerate about 15% erroneous codewords
+ QUARTILE, // The QR Code can tolerate about 25% erroneous codewords
+ HIGH , // The QR Code can tolerate about 30% erroneous codewords
+ };
+
+
+ // Returns a value in the range 0 to 3 (unsigned 2-bit integer).
+ private: static int getFormatBits(Ecc ecl);
+
+
+
+ /*---- Static factory functions (high level) ----*/
+
+ /*
+ * Returns a QR Code representing the given Unicode text string at the given error correction level.
+ * As a conservative upper bound, this function is guaranteed to succeed for strings that have 2953 or fewer
+ * UTF-8 code units (not Unicode code points) if the low error correction level is used. The smallest possible
+ * QR Code version is automatically chosen for the output. The ECC level of the result may be higher than
+ * the ecl argument if it can be done without increasing the version.
+ */
+ public: static QrCode encodeText(const char *text, Ecc ecl);
+
+
+ /*
+ * Returns a QR Code representing the given binary data at the given error correction level.
+ * This function always encodes using the binary segment mode, not any text mode. The maximum number of
+ * bytes allowed is 2953. The smallest possible QR Code version is automatically chosen for the output.
+ * The ECC level of the result may be higher than the ecl argument if it can be done without increasing the version.
+ */
+ public: static QrCode encodeBinary(const std::vector<std::uint8_t> &data, Ecc ecl);
+
+
+ /*---- Static factory functions (mid level) ----*/
+
+ /*
+ * Returns a QR Code representing the given segments with the given encoding parameters.
+ * The smallest possible QR Code version within the given range is automatically
+ * chosen for the output. Iff boostEcl is true, then the ECC level of the result
+ * may be higher than the ecl argument if it can be done without increasing the
+ * version. The mask number is either between 0 to 7 (inclusive) to force that
+ * mask, or -1 to automatically choose an appropriate mask (which may be slow).
+ * This function allows the user to create a custom sequence of segments that switches
+ * between modes (such as alphanumeric and byte) to encode text in less space.
+ * This is a mid-level API; the high-level API is encodeText() and encodeBinary().
+ */
+ public: static QrCode encodeSegments(const std::vector<QrSegment> &segs, Ecc ecl,
+ int minVersion=1, int maxVersion=40, int mask=-1, bool boostEcl=true); // All optional parameters
+
+
+
+ /*---- Instance fields ----*/
+
+ // Immutable scalar parameters:
+
+ /* The version number of this QR Code, which is between 1 and 40 (inclusive).
+ * This determines the size of this barcode. */
+ private: int version;
+
+ /* The width and height of this QR Code, measured in modules, between
+ * 21 and 177 (inclusive). This is equal to version * 4 + 17. */
+ private: int size;
+
+ /* The error correction level used in this QR Code. */
+ private: Ecc errorCorrectionLevel;
+
+ /* The index of the mask pattern used in this QR Code, which is between 0 and 7 (inclusive).
+ * Even if a QR Code is created with automatic masking requested (mask = -1),
+ * the resulting object still has a mask value between 0 and 7. */
+ private: int mask;
+
+ // Private grids of modules/pixels, with dimensions of size*size:
+
+ // The modules of this QR Code (false = light, true = dark).
+ // Immutable after constructor finishes. Accessed through getModule().
+ private: std::vector<std::vector<bool> > modules;
+
+ // Indicates function modules that are not subjected to masking. Discarded when constructor finishes.
+ private: std::vector<std::vector<bool> > isFunction;
+
+
+
+ /*---- Constructor (low level) ----*/
+
+ /*
+ * Creates a new QR Code with the given version number,
+ * error correction level, data codeword bytes, and mask number.
+ * This is a low-level API that most users should not use directly.
+ * A mid-level API is the encodeSegments() function.
+ */
+ public: QrCode(int ver, Ecc ecl, const std::vector<std::uint8_t> &dataCodewords, int msk);
+
+
+
+ /*---- Public instance methods ----*/
+
+ /*
+ * Returns this QR Code's version, in the range [1, 40].
+ */
+ public: int getVersion() const;
+
+
+ /*
+ * Returns this QR Code's size, in the range [21, 177].
+ */
+ public: int getSize() const;
+
+
+ /*
+ * Returns this QR Code's error correction level.
+ */
+ public: Ecc getErrorCorrectionLevel() const;
+
+
+ /*
+ * Returns this QR Code's mask, in the range [0, 7].
+ */
+ public: int getMask() const;
+
+
+ /*
+ * Returns the color of the module (pixel) at the given coordinates, which is false
+ * for light or true for dark. The top left corner has the coordinates (x=0, y=0).
+ * If the given coordinates are out of bounds, then false (light) is returned.
+ */
+ public: bool getModule(int x, int y) const;
+
+
+
+ /*---- Private helper methods for constructor: Drawing function modules ----*/
+
+ // Reads this object's version field, and draws and marks all function modules.
+ private: void drawFunctionPatterns();
+
+
+ // 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);
+
+
+ // 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();
+
+
+ // 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);
+
+
+ // 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);
+
+
+ // 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, bool isDark);
+
+
+ // Returns the color of the module at the given coordinates, which must be in range.
+ private: bool module(int x, int y) const;
+
+
+ /*---- 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: std::vector<std::uint8_t> addEccAndInterleave(const std::vector<std::uint8_t> &data) const;
+
+
+ // 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(const std::vector<std::uint8_t> &data);
+
+
+ // 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.
+ private: void applyMask(int msk);
+
+
+ // 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.
+ private: long getPenaltyScore() const;
+
+
+
+ /*---- 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.
+ private: std::vector<int> getAlignmentPatternPositions() const;
+
+
+ // 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.
+ private: static int getNumRawDataModules(int ver);
+
+
+ // 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.
+ private: static int getNumDataCodewords(int ver, Ecc ecl);
+
+
+ // 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 std::vector<std::uint8_t> reedSolomonComputeDivisor(int degree);
+
+
+ // Returns the Reed-Solomon error correction codeword for the given data and divisor polynomials.
+ private: static std::vector<std::uint8_t> reedSolomonComputeRemainder(const std::vector<std::uint8_t> &data, const std::vector<std::uint8_t> &divisor);
+
+
+ // Returns the product of the two given field elements modulo GF(2^8/0x11D).
+ // All inputs are valid. This could be implemented as a 256*256 lookup table.
+ private: static std::uint8_t reedSolomonMultiply(std::uint8_t x, std::uint8_t y);
+
+
+ // Can only be called immediately after a light run is added, and
+ // returns either 0, 1, or 2. A helper function for getPenaltyScore().
+ private: int finderPenaltyCountPatterns(const std::array<int,7> &runHistory) const;
+
+
+ // Must be called at the end of a line (row or column) of modules. A helper function for getPenaltyScore().
+ private: int finderPenaltyTerminateAndCount(bool currentRunColor, int currentRunLength, std::array<int,7> &runHistory) const;
+
+
+ // Pushes the given value to the front and drops the last value. A helper function for getPenaltyScore().
+ private: void finderPenaltyAddHistory(int currentRunLength, std::array<int,7> &runHistory) const;
+
+
+ // Returns true iff the i'th bit of x is set to 1.
+ private: static bool getBit(long x, int i);
+
+
+ /*---- Constants and tables ----*/
+
+ // The minimum version number supported in the QR Code Model 2 standard.
+ public: static constexpr int MIN_VERSION = 1;
+
+ // The maximum version number supported in the QR Code Model 2 standard.
+ public: static constexpr int MAX_VERSION = 40;
+
+
+ // For use in getPenaltyScore(), when evaluating which mask is best.
+ private: static const int PENALTY_N1;
+ private: static const int PENALTY_N2;
+ private: static const int PENALTY_N3;
+ private: static const int PENALTY_N4;
+
+
+ private: static const std::int8_t ECC_CODEWORDS_PER_BLOCK[4][41];
+ private: static const std::int8_t NUM_ERROR_CORRECTION_BLOCKS[4][41];
+
+};
+
+
+
+/*---- Public exception class ----*/
+
+/*
+ * Thrown when the supplied data does not fit any QR Code version. Ways to handle this exception include:
+ * - Decrease the error correction level if it was greater than Ecc::LOW.
+ * - If the encodeSegments() function was called with a maxVersion argument, then increase
+ * it if it was less than QrCode::MAX_VERSION. (This advice does not apply to the other
+ * factory functions because they search all versions up to QrCode::MAX_VERSION.)
+ * - Split the text data into better or optimal segments in order to reduce the number of bits required.
+ * - Change the text or binary data to be shorter.
+ * - Change the text to fit the character set of a particular segment mode (e.g. alphanumeric).
+ * - Propagate the error upward to the caller/user.
+ */
+class data_too_long : public std::length_error {
+
+ public: explicit data_too_long(const std::string &msg);
+
+};
+
+
+
+/*
+ * An appendable sequence of bits (0s and 1s). Mainly used by QrSegment.
+ */
+class BitBuffer final : public std::vector<bool> {
+
+ /*---- Constructor ----*/
+
+ // Creates an empty bit buffer (length 0).
+ public: BitBuffer();
+
+
+
+ /*---- Method ----*/
+
+ // Appends the given number of low-order bits of the given value
+ // to this buffer. Requires 0 <= len <= 31 and val < 2^len.
+ public: void appendBits(std::uint32_t val, int len);
+
+};
+
+}
projects / mirrors / factory_tool.git / commitdiff
