PHP to add an overlay to a random bg image

test.php

<?php
// Get the requested image filename from the query parameter
if (isset($_GET['image'])) {
    $requestedImage = $_GET['image'];

    // Check if the requested image exists in the 'images' folder
    $imagesDir = 'images/';
    $requestedImagePath = $imagesDir . $requestedImage;

    if (file_exists($requestedImagePath)) {
        $randomImage = $requestedImagePath;
    } else {
        die('Requested image not found.');
    }
} else {
    // If no specific image is requested, select a random background image
    $images = glob('images/*.{jpg,jpeg,png}', GLOB_BRACE);

    if (empty($images)) {
        die('No images found in the folder.');
    }

    $randomImage = $images[array_rand($images)];
}

// Load the selected background image
$imageInfo = pathinfo($randomImage);
$imageExtension = strtolower($imageInfo['extension']);

if ($imageExtension === 'jpg' || $imageExtension === 'jpeg') {
    $bg = imagecreatefromjpeg($randomImage);
} elseif ($imageExtension === 'png') {
    $bg = imagecreatefrompng($randomImage);
} else {
    die('Unsupported image format.');
}

// Define the desired size (1280x720)
$newWidth = 1280;
$newHeight = 720;

// Create a new image with the desired size
$resizedBg = imagecreatetruecolor($newWidth, $newHeight);

// Resize and crop the original background image to fit the desired size
imagecopyresampled($resizedBg, $bg, 0, 0, 0, 0, $newWidth, $newHeight, imagesx($bg), imagesy($bg));

// Load the overlay PNG image with transparency
$overlay = imagecreatefrompng('overlay.png');

// Get the dimensions of the overlay image
$overlay_width = imagesx($overlay);
$overlay_height = imagesy($overlay);

// Calculate the position to place the overlay image (you can adjust this)
$pos_x = 0;
$pos_y = 0;

// Merge the overlay image onto the resized background
imagecopy($resizedBg, $overlay, $pos_x, $pos_y, 0, 0, $overlay_width, $overlay_height);

// Set the content type to JPEG
header('Content-Type: image/jpeg');

// Output the resulting image as JPEG
imagejpeg($resizedBg);

// Free up memory
imagedestroy($bg);
imagedestroy($resizedBg);
imagedestroy($overlay);
?>