Advanced Laravel CAPTCHA image generator

A lightweight, high-performance CAPTCHA generation package for Laravel. It produces wave-distorted, GD-based CAPTCHA image streams with fast bitwise transformations, zero runtime asset dependencies, and simple integration with Laravel's Validator.

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Features

• Fast & Lightweight: Employs bitwise color blending and fast bilinear pixel transformations for rapid rendering.
• Zero-Config Default: Works out-of-the-box using the bundled TrueType font inside resources/fonts/.
• Integrated Route & Controller: Serves dynamic binary PNG images via a dedicated endpoint.
• Custom Validation Rule: Integrates natively into Laravel form validation via 'captcha'.
• Session Timeout Protection: Prevents replay attacks with automatic expiration tracking.
• Fully Customizable: Easily configure dimensions, colors, character lengths, font choices, and wave distortion noise.

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Requirements

• PHP: ^8.2 | ^8.3 | ^8.4 | ^8.5
• Laravel Framework: ^11.0 | ^12.0 | ^13.0
• PHP Extensions: ext-gd

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Installation

You can install the package via Composer:

composer require imicodewarlock/captcha

The package service provider and route endpoints will automatically register via Laravel's Package Discovery.

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Configuration & Publishing

Publish the configuration file and optional font assets to your host application using Artisan:

# Publish configuration
php artisan vendor:publish --tag="captcha-config"

# Publish font assets (Optional)
php artisan vendor:publish --tag="captcha-fonts"

This will create config/captcha.php in your application root:

return [
    // Custom absolute font path (defaults to bundled font when null)
    'font' => null,

    // Canvas & Word Dimensions
    'width' => 239,
    'height' => 70,
    'wordlen' => 5,
    'use_numbers' => true,
    'font_size' => 25,

    // Noise & Wave Distortion Parameters
    'line_noise_level' => 5,
    'line_thickness' => 5,
    'dot_noise_level' => 100,
    'dot_size' => 2,
    'frequence' => [700000, 1000000, 40000000],

    // Expiration Parameters (seconds)
    'timeout' => 360,
    'name' => 'captcha',

    // RGBA Color Palettes [R, G, B, Alpha]
    'line_color' => [200, 200, 200, 80],
    'dot_color' => [200, 200, 200, 80],
    'background_color' => [11, 11, 11, 1],
    'font_color' => [255, 255, 255, 1],
];

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Usage

1. Rendering the CAPTCHA in Views

The package automatically registers the /captcha/image route named captcha.image. Use this route inside your Blade templates:

<form method="POST" action="/submit-form">
    @csrf

    <!-- CAPTCHA Image Stream -->
    <div class="captcha-container">
        <img src="{{ route('captcha.image') }}" id="captcha-img" alt="CAPTCHA">
        <button type="button" onclick="document.getElementById('captcha-img').src='{{ route('captcha.image') }}?' + Math.random()">
            Refresh
        </button>
    </div>

    <!-- User Input Field -->
    <input type="text" name="captcha" placeholder="Enter CAPTCHA code" required>
    @error('captcha')
        <span class="error">{{ $message }}</span>
    @enderror

    <button type="submit">Submit</button>
</form>

2. Form Validation

Validate the user input in your Controller or Form Request using the 'captcha' rule:

Controller Example:

use Illuminate\Http\Request;

public function store(Request $request)
{
    $request->validate([
        'captcha' => 'required|captcha',
    ]);

    // Validation passed!
    return back()->with('success', 'CAPTCHA validated successfully!');
}

Form Request Example:

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class SubmitFormRequest extends FormRequest
{
    public function authorize(): bool
    {
        return true;
    }

    public function rules(): array
    {
        return [
            'captcha' => ['required', 'captcha'],
        ];
    }
}

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Testing

Run the package test suite locally using PHPUnit:

composer test
# or directly via PHPUnit
vendor/bin/phpunit