scanlite 0.1.1

Cross-platform document scanner: crop, perspective-correct, enhance, OCR, and combine into PDF.

Scanlite

Turn photos of documents into clean, searchable PDFs.

Load scanned pages or photos from your phone, let Scanlite straighten, crop, and clean them automatically, reorder as needed, and export a single PDF with an optional OCR text layer.

Getting Started

pip install scanlite
scanlite

Or download a native installer from Releases:

Platform	Download	Install
Windows x64	Scanlite-0.1.1.msi	Double-click; installs to Program Files with Start Menu shortcut
macOS Apple Silicon	Scanlite-0.1.1.dmg	Open, drag to Applications
Debian / Ubuntu	scanlite-0.1.1.deb	sudo dpkg -i scanlite-0.1.1.deb
Fedora / RHEL	scanlite-0.1.1.rpm	sudo rpm -i scanlite-0.1.1.rpm

Native installers bundle Tesseract for OCR out of the box. When installing via pip, Tesseract must be available on your system PATH for the OCR export to work.

Features

Import

• PDF (rendered at 200 DPI), PNG, JPG, TIFF, BMP, WebP
• Multi-page PDFs split into individual pages automatically
• Drag-and-drop support (when tkdnd is available)

Processing

• Auto-crop: Otsu threshold + contour detection trims to the document edge

• Auto-perspective: Canny edge detection finds a 4-point quadrilateral and warps it flat

• Scan enhance: three modes that produce a clean, scanner-like look:

  Mode	What it does
  auto	Detects page brightness; picks B&W for white pages, CLAHE for darker ones
  bw	Adaptive Gaussian threshold for pure black-on-white text
  gray	CLAHE contrast enhancement for photos or diagrams

• Every operation works per-page or as a batch across all pages

• Reset any page to its original at any time

Reorder and Manage

• Move Up / Move Down (or arrow keys) to reorder
• Delete to remove a page
• Thumbnail panel shows the current page order at a glance

Export

• PDF: combines all pages into a single document
• PDF + OCR: Tesseract generates an invisible text layer per page, making the output searchable and copy-pasteable
• Keyboard shortcuts: Ctrl+S export, Ctrl+Shift+S export with OCR

Keyboard Shortcuts

Key	Action
Ctrl+O	Import files
Up / Down	Navigate pages
Delete	Remove selected page
Ctrl+S	Export PDF
Ctrl+Shift+S	Export PDF + OCR

How It Works

Scanlite's processing pipeline runs perspective correction first (to avoid cropping a skewed quad), then crop, then enhancement. Each step is independent and can be applied or skipped per page.

The perspective detector looks for the largest 4-sided contour in the edge map and computes a homography to warp it into a rectangle. If no quadrilateral is found, the image passes through unchanged.

The scan enhancer auto-detects whether a page is mostly white (median brightness > 170) and picks adaptive thresholding for text-heavy pages or CLAHE for photos and diagrams.

System Requirements

• Python 3.10+
• Tesseract OCR (bundled in native installers; for pip installs, install separately)

Support

"Software is like sex: it's better when it's free." -- Linus Torvalds

If this tool saved you a trip to the copy shop, buying me a coffee is a nice way to say thanks.

License

MIT (see LICENSE.md)

Citation

@software{scanlite,
  author = {Colling, Gilles},
  title = {Scanlite: Cross-Platform Document Scanner},
  year = {2026},
  url = {https://github.com/gcol33/scanlite}
}