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Scanner Effect

docs/tools/scanner-effect.md

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Scanner Effect

Transform a clean digital PDF into something that looks like it came out of a flatbed scanner. The tool applies configurable noise, slight rotation, blur, brightness shifts, and optional yellowing to simulate the imperfections of a physical scan.

How It Works

  1. Upload your PDF file.
  2. The editor opens with a live preview of the first page alongside a settings panel.
  3. Adjust the scan effect parameters using the sliders and toggles.
  4. The preview updates in real time as you change settings.
  5. Click Apply to process all pages and download the result.

Options

  • Colorspace (Grayscale toggle) -- Convert the output to grayscale for a classic black-and-white scan look.
  • Border -- Add a subtle dark border around the page edges to mimic scanner border artifacts.
  • Rotate -- Apply a slight rotation (-5 to +5 degrees) to simulate misaligned paper feeding.
  • Rotate Variance -- Add random variation to the rotation angle so each page tilts slightly differently.
  • Brightness -- Shift the overall brightness up or down.
  • Contrast -- Adjust contrast to simulate toner quality variations.
  • Blur -- Apply Gaussian blur to soften text edges like a low-quality scan.
  • Noise -- Add random pixel noise to simulate scanner sensor grain. Higher values produce grainier results.
  • Yellowish -- Add a warm yellow tint to simulate aged or recycled paper.
  • Resolution -- Set the output DPI. Lower values create a more pixelated, scan-like appearance.
  • Reset -- Restore all settings to their defaults.

Features

  • Real-time preview that updates as you tweak each parameter
  • Per-page random rotation variance for realistic variation
  • Ten independently adjustable parameters
  • Grayscale mode for authentic black-and-white scan output
  • Resolution control from low-DPI fax quality to high-DPI archive quality

Use Cases

  • Making digitally created documents appear to have been scanned and printed
  • Simulating physical document aging for historical document recreation
  • Testing OCR software against degraded scan quality
  • Producing documents that match the visual style of existing scanned archives

Tips

  • Start with subtle values. A noise level of 10-20, a slight 0.5-degree rotation, and minimal blur already produce a convincing scan look.
  • Combine grayscale mode with slight yellowing for a "photocopy of a photocopy" effect.
  • Lower resolution settings (100-150 DPI) create the most realistic fax-machine appearance.