Professional WordPress image optimization plugin showcasing advanced PHP, OOP, and WordPress development skills.

ODR Image Optimizer is a production-ready WordPress plugin demonstrating enterprise-level development practices. It provides intelligent image compression, WebP conversion, lazy loading, and REST API integration.

Perfect for: Portfolio showcasing, job interviews, freelance projects, or WordPress.org marketplace submission.

Desktop Dashboard	Mobile Responsive

The admin dashboard provides real-time statistics, visual library view, and one-click optimization for individual or bulk operations.

• Multi-level compression (Low/Medium/High quality settings)
• Format support: JPEG, PNG, GIF, WebP
• Smart optimization based on image type
• Quality preservation while reducing file size
• Batch processing for large libraries

• WebP conversion with browser fallbacks
• Lazy loading with Intersection Observer
• Async optimization for non-blocking operations
• Caching layer for improved dashboard performance
• Indexed database queries for scale

• Real-time statistics (images optimized, savings)
• Visual library view with optimization status
• One-click optimization for individual/bulk operations
• Responsive design (desktop & mobile)
• Export capabilities for reporting

Complete REST API for programmatic access:

• GET /wp-json/image-optimizer/v1/stats - Statistics
• GET /wp-json/image-optimizer/v1/images - Image list
• POST /wp-json/image-optimizer/v1/optimize/{id} - Optimize image
• GET /wp-json/image-optimizer/v1/history/{id} - Optimization history

• Compression level configuration
• WebP conversion toggle
• Lazy loading options
• Auto-optimization on upload
• Granular control

Backend

• PHP 7.4+ with OOP design patterns
• WordPress plugin architecture
• Custom database tables
• REST API implementation

Database

• MySQL 5.6+ with indexed queries
• Custom tables for optimization history
• Performance-optimized schema

Frontend

• Vanilla JavaScript (no jQuery dependency)
• Responsive CSS Grid
• Intersection Observer API
• Progressive enhancement

odr-image-optimizer/
├── odr-image-optimizer.php          # Main plugin file
├── README.md                        # User documentation
├── CONTRIBUTING.md                  # Contribution guidelines
├── CHANGELOG.md                     # Version history
├── LICENSE                          # GPL v2+ license
├── docs/
│   ├── DEVELOPMENT.md               # Developer guide & architecture
│   └── COMMIT_CONVENTION.md         # Git commit standards
├── includes/
│   ├── class-autoloader.php         # PSR-4 autoloader
│   ├── class-core.php               # Main plugin class (Singleton)
│   ├── core/
│   │   ├── class-api.php            # REST API endpoints
│   │   ├── class-database.php       # Database layer
│   │   └── class-optimizer.php      # Image optimization engine
│   └── admin/
│       ├── class-dashboard.php      # Admin dashboard
│       └── class-settings.php       # Settings page
├── assets/
│   ├── css/
│   │   ├── admin.css                # Admin styles
│   │   ├── public.css               # Frontend styles
│   │   └── dashboard.css            # Dashboard gallery styles
│   └── js/
│       ├── admin.js                 # Admin functionality
│       ├── public.js                # Frontend functionality
│       ├── dashboard.js             # Dashboard interactions
│       └── lazy-load.js             # Lazy loading implementation
├── languages/                       # Localization files
├── admin/                           # Additional admin files
├── public/                          # Frontend classes
└── package.json                     # NPM dependencies & scripts

├── composer.json # Project metadata ├── LICENSE # GPL v2 license ├── .gitignore # Git ignore patterns ├── includes/ │ ├── class-autoloader.php # PSR-4 autoloader │ ├── class-core.php # Main orchestrator │ ├── admin/ │ │ ├── class-dashboard.php # Admin UI │ │ └── class-settings.php # Settings page │ └── core/ │ ├── class-optimizer.php # Compression engine │ ├── class-database.php # Database layer │ └── class-api.php # REST API ├── assets/ │ ├── css/ │ │ ├── dashboard.css │ │ └── settings.css │ └── js/ │ └── lazy-load.js └── languages/ └── image-optimizer.pot # Translation template

## 🚀 Quick Start

### Installation

1. **Clone repository**
   ```bash
   git clone https://github.com/odanree/odr-image-optimizer.git
   cd odr-image-optimizer

2. Copy to WordPress

   cp -r . /path/to/wp-content/plugins/odr-image-optimizer/

3. Activate plugin

   • Navigate to WordPress admin → Plugins
   • Find "ODR Image Optimizer"
   • Click "Activate"

4. Configure

   • Go to ODR Image Optimizer → Settings
   • Choose compression level
   • Enable WebP conversion (optional)
   • Enable lazy loading (optional)

Dashboard:

1. Navigate to ODR Image Optimizer → Dashboard
2. View your media library with optimization status
3. Click "Optimize" on any image or select multiple for bulk operation
4. Monitor statistics and compression results

Settings:

1. Navigate to ODR Image Optimizer → Settings
2. Adjust compression level (Low/Medium/High)
3. Toggle WebP conversion
4. Toggle lazy loading
5. Save changes

REST API:

# Get statistics
curl http://localhost:8000/wp-json/image-optimizer/v1/stats

# List images
curl http://localhost:8000/wp-json/image-optimizer/v1/images

# Optimize image
curl -X POST http://localhost:8000/wp-json/image-optimizer/v1/optimize/123

# Get history
curl http://localhost:8000/wp-json/image-optimizer/v1/history/123

Singleton Pattern

// Clean instance management
$plugin = Core::get_instance();

PSR-4 Autoloading

// Automatic class loading
namespace ImageOptimizer\Core;
class Optimizer {} // Auto-loaded from includes/core/class-optimizer.php

Custom Database Tables

// Indexed queries for performance
$wpdb->prepare("SELECT * FROM {$table} WHERE attachment_id = %d", $id);

REST API

// Full REST implementation with permissions
register_rest_route('image-optimizer/v1', '/optimize/(?P<attachment_id>\d+)', [
    'methods' => 'POST',
    'callback' => [$this, 'optimize_image'],
    'permission_callback' => [$this, 'check_admin_permission']
]);

✅ Nonce Verification - All form submissions ✅ Capability Checks - manage_options required ✅ Input Sanitization - All user inputs ✅ Output Escaping - All user output ✅ SQL Prepared Statements - No raw queries ✅ Direct Access Prevention - File existence checks

• Follows WordPress Coding Standards
• Proper namespacing and escaping
• Appropriate hooks and filters
• Comprehensive inline documentation
• PHPDoc comments on all methods

Test Setup: 5 high-resolution images (2.5 MB unoptimized), mobile 4G + 4x CPU throttle

Key Finding: Disabling the plugin caused performance to revert to the unoptimized baseline (82, 4.4s), proving 100% of the improvement is from the plugin's image optimization.

• Database Overhead: Minimal (~100 bytes per record)
• Query Time: <10ms average with indexes
• Image Processing: Non-blocking async operations
• Memory Usage: Optimized streaming for large files
• Lazy Loading: ~30% reduction in initial page load
• Featured Image Optimization: 95% size reduction (1920x1280 → 300x200)

With the plugin achieving 91 Performance score on mobile:

• ✅ Google Core Web Vitals: All green (Good LCP, stable CLS)
• ✅ User Experience: 30% faster LCP = better engagement
• ✅ SEO: Better indexing from Google with Core Web Vitals compliance
• ✅ Mobile Users: 1.3 second faster load = reduced bounce rate

# Install dependencies
composer install --dev

# Check code standards
composer run phpcs

# Auto-fix code standards
composer run phpcbf

This project strictly follows WordPress Coding Standards. Check your code:

phpcs --standard=WordPress image-optimizer.php includes/

1. Upload test images (JPEG, PNG, GIF)
2. Verify optimization in database
3. Check WebP files created
4. Test bulk operations
5. Verify REST API endpoints

Add Custom Optimization Method:

add_filter('image_optimizer_methods', function($methods) {
    $methods['custom'] = 'My_Custom_Optimizer';
    return $methods;
});

Add Custom REST Endpoint:

add_action('rest_api_init', function() {
    register_rest_route('image-optimizer/v1', '/analyze', [
        'methods' => 'POST',
        'callback' => 'my_custom_callback',
        'permission_callback' => '__return_true'
    ]);
});

• README.md - User guide and features
• CONTRIBUTING.md - Contribution guidelines
• CHANGELOG.md - Version history
• docs/DEVELOPMENT.md - Developer guide and architecture
• docs/COMMIT_CONVENTION.md - Git commit standards
• docs/PERFORMANCE_CASE_STUDY.md - Before/after optimization metrics
• docs/LIGHTHOUSE_OPTIMIZATIONS.md - Lighthouse audit fixes

Version 1.1

• AVIF format support
• Background optimization via WP-Cron
• CDN integration

Version 2.0

• AI-powered quality detection
• Advanced image editing
• WooCommerce product optimization

Found a bug or have a feature request?

1. Check existing issues: GitHub Issues
2. Report new issue with:
   • Clear title
   • Detailed description
   • Steps to reproduce
   • WordPress/PHP versions
   • Screenshots if applicable

Contributions are welcome! Please see CONTRIBUTING.md for guidelines.

1. Fork the repository
2. Create feature branch: git checkout -b feature/amazing-feature
3. Commit changes: git commit -m 'Add amazing feature'
4. Push to branch: git push origin feature/amazing-feature
5. Open Pull Request

This plugin is licensed under the GPL v2 or later. See LICENSE for details.

Copyright (C) 2025 Danh Le

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

Danh Le

• 🌐 Website: danhle.net
• 🐙 GitHub: @odanree
• 💼 LinkedIn: Danh Le

Q: Is this production-ready? A: Yes! The plugin follows WordPress best practices and security standards. Used on production sites.

Q: Can I use this commercially? A: Yes! It's GPL v2+, so you can use it in commercial projects. Just maintain the license.

Q: Does it work with all WordPress versions? A: Requires WordPress 5.0+ and PHP 7.4+. Tested up to WordPress 6.9.

Q: How much does it improve performance? A: Verified via Lighthouse testing: +9 performance points (82→91) and 30% LCP improvement (4.4s→3.1s) on mobile with 5 test images. Desktop achieves perfect 100 score. See Performance Metrics section and PERFORMANCE_REPORT.md for details.

Q: Can I extend it? A: Absolutely! It's built with extensibility in mind. Check docs/DEVELOPMENT.md for examples.

Q: Is it actively maintained? A: Yes! Regular updates and security patches are released.

This project demonstrates:

• ✅ Advanced PHP/OOP - Design patterns, namespaces, autoloading
• ✅ WordPress Expertise - Plugin architecture, hooks, REST API
• ✅ Database Design - Schema optimization, indexed queries
• ✅ Performance Engineering - Optimization algorithms, caching
• ✅ Security - Best practices, nonce verification, sanitization
• ✅ Code Quality - Standards compliance, documentation, testing
• ✅ DevOps - Version control, CI/CD ready, deployment best practices

Perfect for job interviews, freelance portfolios, or marketplace submission.

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