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Jyoti Prajapati
Jyoti Prajapati

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Post 1: Implemented Canny Edge Detection, Sobel Operators, and Perspective Transforms from scratch

I was developing a theoretical understanding of computer vision algorithms, from basic to advanced, in order to grasp the mathematics behind them and the result?

I developed A browser-based document scanner that:

  • Auto-detects document boundaries
  • Corrects perspective distortion
  • Enhances image quality
  • Processes images in 2-3 seconds

This is the workflow for the sample application:

Tech: JavaScript + Canvas API + Pure Math

No OpenCV, no ML models - just classical algorithms that have stood the test of time.

This is working sample images:

Github link:

📱 Document Scanner Pro

A browser-based document scanner built with pure Computer Vision algorithms - no external CV libraries!

✨ Features

  • 📸 Camera Capture - Take photos directly from mobile/desktop camera
  • 🖼️ Image Upload - Support for all image formats (JPG, PNG, WEBP, BMP, GIF, TIFF, SVG)
  • 🤖 Auto Detection - Automatic document edge detection and perspective correction
  • 🎨 Multiple Modes - Auto detect, Enhance, or Black & White
  • ⚙️ Adjustable Settings - Custom contrast and brightness controls
  • 📥 Download Results - Save processed documents as JPG
  • 💻 Offline-First - Runs entirely in browser, no backend needed
  • 📱 Mobile-Friendly - Responsive design for all devices

Testing demo:

image

🔬 Computer Vision Algorithms Implemented

This project implements 10+ classical CV algorithms from scratch without using OpenCV or any CV libraries:

Core Algorithms

# Algorithm Purpose Technique
1 Weighted Grayscale Color to grayscale conversion 0.299R + 0.587G + 0.114B
2 Histogram Stretching Contrast

ComputerVision #Algorithms #JavaScript #ImageProcessing

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