What are the common reasons for slow loading times when sending images using PHP readfile() function?

The common reasons for slow loading times when sending images using the PHP readfile() function include large image file sizes, inefficient server configurations, and network latency. To improve loading times, consider optimizing image sizes, enabling caching, and using a content delivery network (CDN) to reduce latency.

<?php
// Enable output buffering to improve loading times
ob_start();

// Send image using readfile() function
$image_path = 'path/to/image.jpg';
header('Content-Type: image/jpeg');
readfile($image_path);

// Flush output buffer and send content to the browser
ob_end_flush();