mozilla/pdf.js · error · FormatError

No range.

Error message

No range.

What it means

Thrown by PDFFunction.constructPostScript (FunctionType 4) when /Range is missing or non-numeric, after Domain has already been validated. Range defines the output dimensionality and clipping for the PostScript calculator and is required before the program can be compiled.

Source

Thrown at src/core/function.js:352

        dmin === dmax
          ? rmin
          : rmin + ((v - dmin) * (rmax - rmin)) / (dmax - dmin);

      // call the appropriate function
      fns[i](tmpBuf, 0, dest, destOffset);
    };
  }

  static constructPostScript(factory, fn, dict) {
    const domain = toNumberArray(dict.getArray("Domain"));
    const range = toNumberArray(dict.getArray("Range"));

    if (!domain) {
      throw new FormatError("No domain.");
    }

    if (!range) {
      throw new FormatError("No range.");
    }

    const psCode = fn.getString();

    try {
      if (factory.useWasm) {
        const wasmFn = buildPostScriptWasmFunction(psCode, domain, range);
        if (wasmFn) {
          return wasmFn; // (src, srcOffset, dest, destOffset) → void
        }
      }
    } catch {}

    warn("Failed to compile PostScript function to wasm, falling back to JS");

    return buildPostScriptJsFunction(psCode, domain, range);
  }
}

View on GitHub (pinned to 5903d58d58)

Solutions

1. Emit /Range as a flat numeric array of even length for every Type 4 function when generating PDFs.
2. Validate the PDF in Acrobat and report discrepancies to pdf.js.
3. Catch FormatError around the render pipeline and skip the affected page.
4. Use qpdf --check or a PDF/A validator to flag the missing required entry.

function postScriptHasRange(dict) {
  const r = dict.getArray?.('Range');
  return Array.isArray(r) && r.every(Number.isFinite) && r.length % 2 === 0;
}

function isNumericIntervalArray(arr) {
  return Array.isArray(arr) && arr.length % 2 === 0 &&
    arr.every(x => typeof x === 'number' && Number.isFinite(x));
}

try { await page.render({ canvasContext }).promise; }
catch (err) {
  if (err?.name === 'FormatError' && err.message === 'No range.') {
    console.warn('PostScript function missing range; skipping.');
  } else throw err;
}

When it happens

Trigger: A FunctionType 4 stream with a valid Domain but missing/non-numeric Range. Encountered during compilation of a PostScript calculator function referenced by a shading or Indexed color space.

Common situations: Incomplete Type 4 functions from buggy PDF generators; truncated object streams after a merge; ICC profile-driven gradients where Range was omitted.

Related errors

• No domain.
• Unknown function type: ${typeNum}
• No domain or range
• No domain
• Bad domain for stiched function

AI-assisted analysis of mozilla/pdf.js@5903d58d58 (2026-08-13). Data as JSON: /api/errors/da008c1fdedab512. Report an issue: GitHub.