Clean up photos and scans of handwritten homework, lecture notes, and engineering calculations by stripping away printed background paper lines. Writing on standard ruled or quadrille graph notebooks introduces distracting cyan lines and red margins that interfere with OCR scanning, document export, and digital archiving.

This tool isolates and removes ruled paper lines by analyzing RGB color thresholds and pixel luminance on an HTML5 canvas. It identifies blue or cyan ruled lines where the blue color channel significantly exceeds red and green, alongside pink or red vertical margin rules. Pixels matching the line profile are replaced with pure white paper background, while graphite pencil marks and dark ink strokes are boosted to preserve sharp letterforms.

For example, uploading a phone photo of calculus notes with blue horizontal rulings and adjusting the line sensitivity slider strips out the background grid while keeping the dark blue and black pen strokes legible on a clean white page.

All pixel manipulation executes locally in your web browser using HTML5 Canvas 2D image data. Your notes and photographs never leave your computer.