diff --git a/src/third_party/QR-Code-generator/cpp/QrCode.cpp b/src/third_party/QR-Code-generator/cpp/QrCode.cpp
new file mode 100644
index 0000000..75a5473
--- /dev/null
+++ b/src/third_party/QR-Code-generator/cpp/QrCode.cpp
@@ -0,0 +1,616 @@
+/* 
+ * 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 <climits>
+#include <cstddef>
+#include <cstdlib>
+#include <sstream>
+#include <utility>
+#include "BitBuffer.hpp"
+#include "QrCode.hpp"
+
+using std::int8_t;
+using std::uint8_t;
+using std::size_t;
+using std::vector;
+
+
+namespace qrcodegen {
+
+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 "Assertion error";
+	}
+}
+
+
+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 "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
+			throw "Data too long";
+	}
+	if (dataUsedBits == -1)
+		throw "Assertion error";
+	
+	// Increase the error correction level while the data still fits in the current version number
+	for (Ecc newEcl : vector<Ecc>{Ecc::MEDIUM, Ecc::QUARTILE, Ecc::HIGH}) {
+		if (boostEcl && dataUsedBits <= getNumDataCodewords(version, newEcl) * 8)
+			ecl = newEcl;
+	}
+	
+	// Create the data bit string by concatenating all segments
+	size_t dataCapacityBits = getNumDataCodewords(version, ecl) * 8;
+	BitBuffer bb;
+	for (const QrSegment &seg : segs) {
+		bb.appendBits(seg.getMode().getModeBits(), 4);
+		bb.appendBits(seg.getNumChars(), seg.getMode().numCharCountBits(version));
+		bb.insert(bb.end(), seg.getData().begin(), seg.getData().end());
+	}
+	
+	// Add terminator and pad up to a byte if applicable
+	bb.appendBits(0, std::min<size_t>(4, dataCapacityBits - bb.size()));
+	bb.appendBits(0, (8 - bb.size() % 8) % 8);
+	
+	// Pad with alternate bytes until data capacity is reached
+	for (uint8_t padByte = 0xEC; bb.size() < dataCapacityBits; padByte ^= 0xEC ^ 0x11)
+		bb.appendBits(padByte, 8);
+	if (bb.size() % 8 != 0)
+		throw "Assertion error";
+	
+	// Create the QR Code symbol
+	return QrCode(version, ecl, bb.getBytes(), mask);
+}
+
+
+QrCode::QrCode(int ver, Ecc ecl, const vector<uint8_t> &dataCodewords, int mask) :
+		// Initialize fields
+		version(ver),
+		size(MIN_VERSION <= ver && ver <= MAX_VERSION ? ver * 4 + 17 : -1),  // Avoid signed overflow undefined behavior
+		errorCorrectionLevel(ecl),
+		modules(size, vector<bool>(size)),  // Entirely white grid
+		isFunction(size, vector<bool>(size)) {
+	
+	// Check arguments
+	if (ver < MIN_VERSION || ver > MAX_VERSION || mask < -1 || mask > 7)
+		throw "Value out of range";
+	
+	// Draw function patterns, draw all codewords, do masking
+	drawFunctionPatterns();
+	const vector<uint8_t> allCodewords = appendErrorCorrection(dataCodewords);
+	drawCodewords(allCodewords);
+	this->mask = handleConstructorMasking(mask);
+}
+
+
+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);
+}
+
+
+std::string QrCode::toSvgString(int border) const {
+	if (border < 0)
+		throw "Border must be non-negative";
+	if (border > INT_MAX / 2 || border * 2 > INT_MAX - size)
+		throw "Border too large";
+	
+	std::ostringstream sb;
+	sb << "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
+	sb << "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.1//EN\" \"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd\">\n";
+	sb << "<svg xmlns=\"http://www.w3.org/2000/svg\" version=\"1.1\" viewBox=\"0 0 ";
+	sb << (size + border * 2) << " " << (size + border * 2) << "\" stroke=\"none\">\n";
+	sb << "\t<rect width=\"100%\" height=\"100%\" fill=\"#FFFFFF\"/>\n";
+	sb << "\t<path d=\"";
+	bool head = true;
+	for (int y = -border; y < size + border; y++) {
+		for (int x = -border; x < size + border; x++) {
+			if (getModule(x, y)) {
+				if (head)
+					head = false;
+				else
+					sb << " ";
+				sb << "M" << (x + border) << "," << (y + border) << "h1v1h-1z";
+			}
+		}
+	}
+	sb << "\" fill=\"#000000\"/>\n";
+	sb << "</svg>\n";
+	return sb.str();
+}
+
+
+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(version);
+	int numAlign = alignPatPos.size();
+	for (int i = 0; i < numAlign; i++) {
+		for (int j = 0; j < numAlign; j++) {
+			if ((i == 0 && j == 0) || (i == 0 && j == numAlign - 1) || (i == numAlign - 1 && j == 0))
+				continue;  // Skip the three finder corners
+			else
+				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 mask) {
+	// Calculate error correction code and pack bits
+	int data = getFormatBits(errorCorrectionLevel) << 3 | mask;  // errCorrLvl is uint2, mask is uint3
+	int rem = data;
+	for (int i = 0; i < 10; i++)
+		rem = (rem << 1) ^ ((rem >> 9) * 0x537);
+	data = data << 10 | rem;
+	data ^= 0x5412;  // uint15
+	if (data >> 15 != 0)
+		throw "Assertion error";
+	
+	// Draw first copy
+	for (int i = 0; i <= 5; i++)
+		setFunctionModule(8, i, ((data >> i) & 1) != 0);
+	setFunctionModule(8, 7, ((data >> 6) & 1) != 0);
+	setFunctionModule(8, 8, ((data >> 7) & 1) != 0);
+	setFunctionModule(7, 8, ((data >> 8) & 1) != 0);
+	for (int i = 9; i < 15; i++)
+		setFunctionModule(14 - i, 8, ((data >> i) & 1) != 0);
+	
+	// Draw second copy
+	for (int i = 0; i <= 7; i++)
+		setFunctionModule(size - 1 - i, 8, ((data >> i) & 1) != 0);
+	for (int i = 8; i < 15; i++)
+		setFunctionModule(8, size - 15 + i, ((data >> i) & 1) != 0);
+	setFunctionModule(8, size - 8, true);
+}
+
+
+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 data = (long)version << 12 | rem;  // uint18
+	if (data >> 18 != 0)
+		throw "Assertion error";
+	
+	// Draw two copies
+	for (int i = 0; i < 18; i++) {
+		bool bit = ((data >> i) & 1) != 0;
+		int a = size - 11 + i % 3, b = i / 3;
+		setFunctionModule(a, b, bit);
+		setFunctionModule(b, a, bit);
+	}
+}
+
+
+void QrCode::drawFinderPattern(int x, int y) {
+	for (int i = -4; i <= 4; i++) {
+		for (int j = -4; j <= 4; j++) {
+			int dist = std::max(std::abs(i), std::abs(j));  // Chebyshev/infinity norm
+			int xx = x + j, yy = y + i;
+			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 i = -2; i <= 2; i++) {
+		for (int j = -2; j <= 2; j++)
+			setFunctionModule(x + j, y + i, std::max(std::abs(i), std::abs(j)) != 1);
+	}
+}
+
+
+void QrCode::setFunctionModule(int x, int y, bool isBlack) {
+	modules.at(y).at(x) = isBlack;
+	isFunction.at(y).at(x) = true;
+}
+
+
+bool QrCode::module(int x, int y) const {
+	return modules.at(y).at(x);
+}
+
+
+vector<uint8_t> QrCode::appendErrorCorrection(const vector<uint8_t> &data) const {
+	if (data.size() != static_cast<unsigned int>(getNumDataCodewords(version, errorCorrectionLevel)))
+		throw "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 ReedSolomonGenerator rs(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 += dat.size();
+		const vector<uint8_t> ecc = rs.getRemainder(dat);
+		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 (int i = 0; static_cast<unsigned int>(i) < blocks.at(0).size(); i++) {
+		for (int j = 0; static_cast<unsigned int>(j) < blocks.size(); j++) {
+			// Skip the padding byte in short blocks
+			if (i != shortBlockLen - blockEccLen || j >= numShortBlocks)
+				result.push_back(blocks.at(j).at(i));
+		}
+	}
+	if (result.size() != static_cast<unsigned int>(rawCodewords))
+		throw "Assertion error";
+	return result;
+}
+
+
+void QrCode::drawCodewords(const vector<uint8_t> &data) {
+	if (data.size() != static_cast<unsigned int>(getNumRawDataModules(version) / 8))
+		throw "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++) {
+				int x = right - j;  // Actual x coordinate
+				bool upward = ((right + 1) & 2) == 0;
+				int y = upward ? size - 1 - vert : vert;  // Actual y coordinate
+				if (!isFunction.at(y).at(x) && i < data.size() * 8) {
+					modules.at(y).at(x) = ((data.at(i >> 3) >> (7 - (i & 7))) & 1) != 0;
+					i++;
+				}
+				// If there are any remainder bits (0 to 7), they are already
+				// set to 0/false/white when the grid of modules was initialized
+			}
+		}
+	}
+	if (static_cast<unsigned int>(i) != data.size() * 8)
+		throw "Assertion error";
+}
+
+
+void QrCode::applyMask(int mask) {
+	if (mask < 0 || mask > 7)
+		throw "Mask value out of range";
+	for (int y = 0; y < size; y++) {
+		for (int x = 0; x < size; x++) {
+			bool invert;
+			switch (mask) {
+				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 "Assertion error";
+			}
+			modules.at(y).at(x) = modules.at(y).at(x) ^ (invert & !isFunction.at(y).at(x));
+		}
+	}
+}
+
+
+int QrCode::handleConstructorMasking(int mask) {
+	if (mask == -1) {  // Automatically choose best mask
+		long minPenalty = LONG_MAX;
+		for (int i = 0; i < 8; i++) {
+			drawFormatBits(i);
+			applyMask(i);
+			long penalty = getPenaltyScore();
+			if (penalty < minPenalty) {
+				mask = i;
+				minPenalty = penalty;
+			}
+			applyMask(i);  // Undoes the mask due to XOR
+		}
+	}
+	if (mask < 0 || mask > 7)
+		throw "Assertion error";
+	drawFormatBits(mask);  // Overwrite old format bits
+	applyMask(mask);  // Apply the final choice of mask
+	return mask;  // The caller shall assign this value to the final-declared field
+}
+
+
+long QrCode::getPenaltyScore() const {
+	long result = 0;
+	
+	// Adjacent modules in row having same color
+	for (int y = 0; y < size; y++) {
+		bool colorX = false;
+		for (int x = 0, runX = -1; x < size; x++) {
+			if (x == 0 || module(x, y) != colorX) {
+				colorX = module(x, y);
+				runX = 1;
+			} else {
+				runX++;
+				if (runX == 5)
+					result += PENALTY_N1;
+				else if (runX > 5)
+					result++;
+			}
+		}
+	}
+	// Adjacent modules in column having same color
+	for (int x = 0; x < size; x++) {
+		bool colorY = false;
+		for (int y = 0, runY = -1; y < size; y++) {
+			if (y == 0 || module(x, y) != colorY) {
+				colorY = module(x, y);
+				runY = 1;
+			} else {
+				runY++;
+				if (runY == 5)
+					result += PENALTY_N1;
+				else if (runY > 5)
+					result++;
+			}
+		}
+	}
+	
+	// 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;
+		}
+	}
+	
+	// Finder-like pattern in rows
+	for (int y = 0; y < size; y++) {
+		for (int x = 0, bits = 0; x < size; x++) {
+			bits = ((bits << 1) & 0x7FF) | (module(x, y) ? 1 : 0);
+			if (x >= 10 && (bits == 0x05D || bits == 0x5D0))  // Needs 11 bits accumulated
+				result += PENALTY_N3;
+		}
+	}
+	// Finder-like pattern in columns
+	for (int x = 0; x < size; x++) {
+		for (int y = 0, bits = 0; y < size; y++) {
+			bits = ((bits << 1) & 0x7FF) | (module(x, y) ? 1 : 0);
+			if (y >= 10 && (bits == 0x05D || bits == 0x5D0))  // Needs 11 bits accumulated
+				result += PENALTY_N3;
+		}
+	}
+	
+	// Balance of black and white modules
+	int black = 0;
+	for (const vector<bool> &row : modules) {
+		for (bool color : row) {
+			if (color)
+				black++;
+		}
+	}
+	int total = size * size;
+	// Find smallest k such that (45-5k)% <= dark/total <= (55+5k)%
+	for (int k = 0; black*20L < (9L-k)*total || black*20L > (11L+k)*total; k++)
+		result += PENALTY_N4;
+	return result;
+}
+
+
+vector<int> QrCode::getAlignmentPatternPositions(int ver) {
+	if (ver < MIN_VERSION || ver > MAX_VERSION)
+		throw "Version number out of range";
+	else if (ver == 1)
+		return vector<int>();
+	else {
+		int numAlign = ver / 7 + 2;
+		int step;
+		if (ver != 32) {
+			// ceil((size - 13) / (2*numAlign - 2)) * 2
+			step = (ver * 4 + numAlign * 2 + 1) / (2 * numAlign - 2) * 2;
+		} else  // C-C-C-Combo breaker!
+			step = 26;
+		
+		vector<int> result;
+		for (int i = 0, pos = ver * 4 + 10; 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 "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 -= 18 * 2;  // Subtract version information
+	}
+	return result;
+}
+
+
+int QrCode::getNumDataCodewords(int ver, Ecc ecl) {
+	if (ver < MIN_VERSION || ver > MAX_VERSION)
+		throw "Version number out of range";
+	return getNumRawDataModules(ver) / 8
+		- ECC_CODEWORDS_PER_BLOCK[static_cast<int>(ecl)][ver]
+		* NUM_ERROR_CORRECTION_BLOCKS[static_cast<int>(ecl)][ver];
+}
+
+
+/*---- 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
+};
+
+
+QrCode::ReedSolomonGenerator::ReedSolomonGenerator(int degree) :
+		coefficients() {
+	if (degree < 1 || degree > 255)
+		throw "Degree out of range";
+	
+	// Start with the monomial x^0
+	coefficients.resize(degree);
+	coefficients.at(degree - 1) = 1;
+	
+	// Compute the product polynomial (x - r^0) * (x - r^1) * (x - r^2) * ... * (x - r^{degree-1}),
+	// drop the highest term, and store the rest of the coefficients in order of descending powers.
+	// 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 < coefficients.size(); j++) {
+			coefficients.at(j) = multiply(coefficients.at(j), root);
+			if (j + 1 < coefficients.size())
+				coefficients.at(j) ^= coefficients.at(j + 1);
+		}
+		root = multiply(root, 0x02);
+	}
+}
+
+
+vector<uint8_t> QrCode::ReedSolomonGenerator::getRemainder(const vector<uint8_t> &data) const {
+	// Compute the remainder by performing polynomial division
+	vector<uint8_t> result(coefficients.size());
+	for (uint8_t b : data) {
+		uint8_t factor = b ^ result.at(0);
+		result.erase(result.begin());
+		result.push_back(0);
+		for (size_t j = 0; j < result.size(); j++)
+			result.at(j) ^= multiply(coefficients.at(j), factor);
+	}
+	return result;
+}
+
+
+uint8_t QrCode::ReedSolomonGenerator::multiply(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;
+	}
+	if (z >> 8 != 0)
+		throw "Assertion error";
+	return static_cast<uint8_t>(z);
+}
+
+}