XRayPDF 🔍✨

XRayPDF is a powerful web application designed to help students uncover hidden text in homework PDFs. Teachers sometimes embed text in tricky ways—using near‑invisible colors, extremely small fonts, or even steganographic tricks. PixelReveal renders each PDF page as an image, then applies a combination of pixel‑level analysis and Optical Character Recognition (OCR) to detect and reveal any hidden content. The result is a new, enhanced image where the hidden text becomes clearly visible.

will replace with actual demo screenshot)

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🚀 Features

• 📤 Upload PDF – Drag‑and‑drop or select a PDF file.
• 🖼️ Page‑by‑Page Rendering – Each page is converted to a high‑resolution image.
• 🔎 Pixel‑Level Analysis – Detects text with near‑background colors, low contrast, or steganographic patterns.
• 🔡 OCR for Tiny Text – Identifies and extracts extremely small fonts (e.g., <8pt).
• 🎨 Revealed Image Generation – Enhances low‑contrast areas, magnifies tiny text regions, or overlays OCR‑extracted text.
• 👁️ Side‑by‑Side Comparison – View original and revealed pages together.
• ⬇️ Download Results – Save the enhanced image for offline study.

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🧠 How It Works

1. Upload PDF
   The user uploads a PDF file. The backend uses pdf.js to render each page to a canvas at a high DPI, producing a sharp image buffer.

2. Pixel Analysis
   The image is processed with sharp to:

   • Stretch contrast to amplify subtle differences.
   • Invert colors to reveal light‑on‑light text.
   • Detect edges that may indicate character shapes.

3. OCR for Tiny Text
   The same page image is fed to tesseract.js. The OCR engine identifies text regions and estimates font sizes. Text smaller than a configurable threshold (e.g., 8pt equivalent) is flagged as “tiny hidden text.”

4. Revealed Image Generation
   Based on the analysis:

   • Low‑contrast areas are enhanced.
   • Tiny text regions are cropped, upscaled, and blended back into the image.
   • Optionally, the OCR‑extracted text can be overlaid in a large, clear font.

5. Display Results
   The original and revealed images are shown side‑by‑side. Users can download the revealed image or toggle different enhancement modes.

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🛠️ Tech Stack

Area	Technology
Frontend	Next.js (App Router), React, Tailwind CSS
Backend	Next.js API routes
PDF Rendering	pdf.js (Mozilla)
Image Processing	sharp
OCR	tesseract.js
Deployment	Vercel (frontend) + optional self‑hosted worker

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📦 Installation

1. Clone the repository

   git clone https://github.com/geneticglitch/xraypdf.git
   cd xraypdf/client