Views and URLs

def captcha_image(request, key, scale=1):
    """
    Serve captcha image for given key with optional scaling.
    
    Parameters:
    - request: HttpRequest object
    - key: str, captcha hashkey from URL
    - scale: int, image scaling factor (1 or 2, default: 1)
    
    Returns:
    HttpResponse: PNG image with appropriate headers
    
    Raises:
    Http404: If captcha key not found or expired
    """

def captcha_audio(request, key):
    """
    Serve captcha audio file for accessibility.
    
    Parameters:
    - request: HttpRequest object  
    - key: str, captcha hashkey from URL
    
    Returns:
    HttpResponse: WAV audio file with appropriate headers
    
    Raises:
    Http404: If captcha key not found, expired, or audio disabled
    
    Requirements:
    - Flite executable must be installed and configured
    - CAPTCHA_FLITE_PATH setting must point to flite binary
    """

def captcha_refresh(request):
    """
    AJAX endpoint for refreshing captcha without page reload.
    
    Parameters:
    - request: HttpRequest object (typically AJAX POST)
    
    Returns:
    JsonResponse: New captcha data including key, image_url, audio_url
    
    Response format:
    {
        'key': str,           # New captcha hashkey
        'image_url': str,     # URL to new captcha image  
        'audio_url': str      # URL to new captcha audio (None if audio disabled)
    }
    """

def getsize(font, text):
    """
    Get text size for different PIL versions.
    
    Parameters:
    - font: PIL font object
    - text: str, text to measure
    
    Returns:
    tuple: (width, height) of rendered text
    """

def makeimg(size):
    """
    Create base image with configured background color.
    
    Parameters:
    - size: tuple, (width, height) for image
    
    Returns:
    PIL.Image: Base image with background color applied
    """

# URL patterns defined in captcha.urls
urlpatterns = [
    # Standard resolution captcha image
    re_path(r'image/(?P<key>\w+)/$', captcha_image, {'scale': 1}, name='captcha-image'),
    
    # High-resolution captcha image (2x scaling)
    re_path(r'image/(?P<key>\w+)@2/$', captcha_image, {'scale': 2}, name='captcha-image-2x'),
    
    # Captcha audio file
    re_path(r'audio/(?P<key>\w+).wav$', captcha_audio, name='captcha-audio'),
    
    # AJAX refresh endpoint
    re_path(r'refresh/$', captcha_refresh, name='captcha-refresh'),
]

# In your main urls.py
from django.urls import path, include

urlpatterns = [
    # ... other patterns
    path('captcha/', include('captcha.urls')),
]

from django.shortcuts import render
from captcha.models import CaptchaStore
from captcha.helpers import captcha_image_url, captcha_audio_url

def contact_view(request):
    # Generate new captcha
    captcha_key = CaptchaStore.generate_key()
    
    context = {
        'captcha_key': captcha_key,
        'captcha_image': captcha_image_url(captcha_key),
        'captcha_audio': captcha_audio_url(captcha_key),
    }
    return render(request, 'contact.html', context)

// Frontend JavaScript for captcha refresh
function refreshCaptcha() {
    fetch('/captcha/refresh/', {
        method: 'POST',
        headers: {
            'X-CSRFToken': getCookie('csrftoken'),
            'Content-Type': 'application/json',
        },
    })
    .then(response => response.json())
    .then(data => {
        // Update captcha image
        document.getElementById('captcha-image').src = data.image_url;
        
        // Update hidden key field
        document.getElementById('id_captcha_0').value = data.key;
        
        // Clear user input
        document.getElementById('id_captcha_1').value = '';
        
        // Update audio link if present
        if (data.audio_url) {
            document.getElementById('captcha-audio').href = data.audio_url;
        }
    });
}

<!-- In your Django template -->
<div class="captcha-container">
    <img id="captcha-image" src="{% url 'captcha-image' captcha_key %}" 
         alt="Captcha Challenge">
    
    <!-- Audio accessibility option -->
    <a id="captcha-audio" href="{% url 'captcha-audio' captcha_key %}">
        Listen to Audio Version
    </a>
    
    <!-- Refresh button -->
    <button type="button" onclick="refreshCaptcha()">
        Refresh Captcha
    </button>
    
    <!-- Hidden field for captcha key -->
    <input type="hidden" name="captcha_0" value="{{ captcha_key }}">
    
    <!-- User input field -->
    <input type="text" name="captcha_1" placeholder="Enter captcha">
</div>

<!-- Serve 2x resolution images for high-DPI displays -->
<img srcset="{% url 'captcha-image' captcha_key %} 1x,
             {% url 'captcha-image-2x' captcha_key %} 2x"
     src="{% url 'captcha-image' captcha_key %}"
     alt="Captcha Challenge">