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Auto Scan Deskew

Detect and auto-correct page rotations and alignments on mobile-photo or scanned PDF sheets instantly.

Upload Skewed Scanned PDF

Utilizes Hough transform edge fitting to probe grid axis and losslessly deskew pages to perfect horizontal alignment.

About This Tool

The PDF Scan Aligner is a mandatory utility for sanitizing tilted digital assets and mobile snapshots.

Documents scanned via physical flatbeds or captured quickly with smartphones often carry subtle rotations. Tilted pages look highly unprofessional, hinder text readability, and cause margins to clip during printing.

This tool utilizes robust Radon Transform and Hough Line detection algorithms to scan gradients and text lines under 20ms. It precisely measures skew down to 0.01 degrees and performs pixel-level Canvas rotation, snapping your receipts, contracts, and booklets back into crisp geometric alignment.

How to Use

  1. Provide skew PDF

    Upload any PDF sheet carrying rotated or poorly aligned scanned documents.

  2. Analyze and tweak

    The engine auto-detects skew angle and draws aligning grids. Tweak angle manually if needed.

  3. Straighten & download

    Click execute to swing pages through a smooth gyroscope transition and download aligned PDF.

Use Cases

Receipt & Contract Archiving

Straighten quick hand-held mobile contract scans before saving them as formal digital PDF archives.

Academic Book Digitizing

Sanitize microfilm book scans where text lines drift out of horizontal margins.

Student Homework Grading

Correct homework snapshots taken by student phones, relaxing the eyes of grading teachers.

Frequently Asked Questions

How is document skew detected?

We run high-speed Hough Line projections on text lines. Since formal prints have clear horizontal spacing patterns, finding the angle with the maximum variance isolates the rotation.

Will this process crop away page edges?

No. The engine calculates the rotated boundary and extends the Canvas using auto-padding, ensuring all margin text remains intact without cropping.

Does it support documents filled with diagrams?

Yes, as long as there is an underlying structure of lines or general paragraphs, our algorithms can accurately lock onto the principal reading angle.

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