Function extractTextOps

src/pdf.js:82–123

* Extract text from PDF content stream operators. * Handles: (text) Tj, [(text)] TJ, Td/Tm for positioning

(stream)

 * Handles: (text) Tj, [(text)] TJ, Td/Tm for positioning
 */
function extractTextOps(stream) {
  const lines = [];
  let currentLine = '';

  // Match BT...ET blocks (text objects)
  const btBlocks = stream.match(/BT[\s\S]*?ET/g);
  if (!btBlocks) return '';

  for (const block of btBlocks) {
    // (string) Tj — show string
    const tjMatches = block.matchAll(/\(([^)]*)\)\s*Tj/g);
    for (const m of tjMatches) {
      currentLine += decodePdfString(m[1]);
    }

    // [...] TJ — show strings with spacing
    const tjArrayMatches = block.matchAll(/\[((?:[^[\]]*|\([^)]*\))*)\]\s*TJ/gi);
    for (const m of tjArrayMatches) {
      const inner = m[1];
      const parts = inner.matchAll(/\(([^)]*)\)|(-?\d+(?:\.\d+)?)/g);
      for (const p of parts) {
        if (p[1] !== undefined) {
          currentLine += decodePdfString(p[1]);
        } else if (p[2] !== undefined) {
          const kern = parseFloat(p[2]);
          if (kern < -100) currentLine += ' ';
        }
      }
    }

    // Td/TD/Tm — text positioning (new line heuristic)
    if (/\d+\s+(?:-?\d+(?:\.\d+)?)\s+T[dD]/g.test(block)) {
      if (currentLine.trim()) {
        lines.push(currentLine.trim());
        currentLine = '';
      }
    }
  }

  if (currentLine.trim()) lines.push(currentLine.trim());
  return lines.join('\n');
}

/**
 * Decode PDF string escapes: \n, \r, \t, \\, \(, \), octal