Are there any best practices or specific functions in PHP to maintain transparency when overlaying PNG images on JPG images?

When overlaying PNG images on JPG images in PHP, it is important to maintain transparency to ensure the overlay looks seamless. One way to achieve this is by using the imagecopymerge() function in PHP, which allows you to merge two images while preserving the alpha channel of the PNG image. By setting the correct parameters for transparency, you can create a visually appealing overlay effect.

$jpgImage = imagecreatefromjpeg('background.jpg');
$pngImage = imagecreatefrompng('overlay.png');

list($width, $height) = getimagesize('overlay.png');

imagecopymerge($jpgImage, $pngImage, 0, 0, 0, 0, $width, $height, 100);

header('Content-Type: image/jpeg');
imagejpeg($jpgImage);

imagedestroy($jpgImage);
imagedestroy($pngImage);