Put watermark on images using PHP

If you are a professional or a newbie photographer you will probably want to protect your photos from being stolen and used for free. Using PHP you can create different types of watermarks on all of your images. I am going to show you a way how to dynamically put a text messages on your images. What you need is a JPG image file and a font file used for generate the watermark message. I am going to use arial font which you can also download.

Below you can find a watermarkImage() image function which takes 3 parameters ($SourceFile, $WaterMarkText, $DestinationFile) and creates an watermarked image from the source image specified. The first parameter - $SourceFile - is the full server path to the JPG image that you are going to watermark. The second one - $WaterMarkText - is the text message that you want to use for the watermark. And the last parameter - $DestinationFile - can either be blank or full server path to a new file which will be the source file with watermark text on it. What this function does is to read the source file, then create a new image object (using the imagecopyresampled() function). Then using the Arial.ttf font file and the imagettftext() function it writes the WaterMarkText onto the image. The last IF statement checks if it should save a new watermarked file or should just display it on the screen.

<?php

function watermarkImage ($SourceFile, $WaterMarkText, $DestinationFile) { 

   list($width, $height) = getimagesize($SourceFile);

   $image_p = imagecreatetruecolor($width, $height);

   $image = imagecreatefromjpeg($SourceFile);

   imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width, $height); 

   $black = imagecolorallocate($image_p, 0, 0, 0);

   $font = 'arial.ttf';

   $font_size = 10; 

   imagettftext($image_p, $font_size, 0, 10, 20, $black, $font, $WaterMarkText);

   if ($DestinationFile<>'') {

      imagejpeg ($image_p, $DestinationFile, 100); 

   } else {

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

      imagejpeg($image_p, null, 100);

   };

   imagedestroy($image); 

   imagedestroy($image_p); 

};

?>

You need to download the arial.ttf file and upload it on your server. Then create a new PHP file and copy and paste the above function in it. Next 4 lines are used to set the Source file, Watermark text message and Destination file. If you want to just display the watermarked image you need to leave the $DestinationFile variable empty ($DestinationFile=''; ). Also please make sure that for source file and destination file you include the full server path and the image file name. If you want to change the position of the watermark message on your images you can chage that line imagettftext($image_p, $font_size, 0, 10, 20, $black, $font, $WaterMarkText);

<?php

$SourceFile = '/home/user/www/images/image1.jpg';

$DestinationFile = '/home/user/www/images/image1-watermark.jpg'; 

$WaterMarkText = 'Copyright phpJabbers.com';

watermarkImage ($SourceFile, $WaterMarkText, $DestinationFile);

?>