QR Code Architecture & Reed-Solomon Error Correction: ISO/IEC 18004 Engineering Guide

Reed-Solomon Error Correction Levels:
Level    Recovery Tolerance   Redundancy Share   Recommended Use Case
─────    ──────────────────   ────────────────   ───────────────────────────────────────
L        ~7% of codewords     ~14% overhead      Clean digital screens, long URLs
M        ~15% of codewords    ~28% overhead      Standard print, brochures, flyers
Q        ~25% of codewords    ~45% overhead      Outdoor signage, warehouse inventory
H        ~30% of codewords    ~60% overhead      Center logo branding, weather exposure

// Scalable Vector SVG QR Code Generator Blueprint in TypeScript
export interface SvgQrOptions {
  matrix: boolean[][]; // 2D boolean array where true = black module
  size: number;        // Physical viewBox dimension in pixels
  fgColor: string;     // Foreground module color
  bgColor: string;     // Background canvas color
  margin?: number;     // Quiet zone module width (default: 4)
}

export function generateSvgQrCode(options: SvgQrOptions): string {
  const { matrix, size, fgColor, bgColor, margin = 4 } = options;
  const moduleCount = matrix.length;
  const totalGrid = moduleCount + margin * 2;
  const moduleSize = size / totalGrid;

  let pathData = '';

  for (let row = 0; row < moduleCount; row++) {
    for (let col = 0; col < moduleCount; col++) {
      if (matrix[row][col]) {
        const x = (col + margin) * moduleSize;
        const y = (row + margin) * moduleSize;
        // Construct SVG path rectangle command for each active module
        pathData += `M${x.toFixed(2)},${y.toFixed(2)}h${moduleSize.toFixed(2)}v${moduleSize.toFixed(2)}h-${moduleSize.toFixed(2)}Z `;
      }
    }
  }

  return `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 ${size} ${size}" width="${size}" height="${size}">
  <rect width="100%" height="100%" fill="${bgColor}"/>
  <path d="${pathData.trim()}" fill="${fgColor}"/>
</svg>`;
}