How do I repeat a watermark image with GD and PHP?

Question

I've created a script that adds a watermark on top of an existing image using PHP. That works all good. I am able to position it on the top left, bottom left, top right, bottom right and centered. I haven't been able to figure out how to repeat the watermark if I wanted to.

I would like to do a repeating watermark like this image:

enter image description here

The code:

function imagecopymerge_alpha($dst_im, $src_im, $dst_x, $dst_y, $src_x, $src_y, $src_w, $src_h, $pct){ 
    // creating a cut resource 
    $cut = imagecreatetruecolor($src_w, $src_h); 

    // copying relevant section from background to the cut resource 
    imagecopy($cut, $dst_im, 0, 0, $dst_x, $dst_y, $src_w, $src_h); 

    // copying relevant section from watermark to the cut resource 
    imagecopy($cut, $src_im, 0, 0, $src_x, $src_y, $src_w, $src_h);

    // insert cut resource to destination image 
    imagecopymerge($dst_im, $cut, $dst_x, $dst_y, 0, 0, $src_w, $src_h, $pct); 
} 


$imagesource    = $image['file_path'];
$watermarkPath  = $settings['watermark'];
$filetype       = substr($imagesource,strlen($imagesource)-4,4);
$filetype       = strtolower($filetype);
$watermarkType  = substr($watermarkPath,strlen($watermarkPath)-4,4);
$watermarkType  = strtolower($watermarkType);

// Let's pretend that $watermark and $image are now GD resources.

$imagewidth         = imagesx($image);
$imageheight        = imagesy($image);  
$watermarkwidth     = imagesx($watermark);
$watermarkheight    = imagesy($watermark);

switch ($settings['watermark_location'])
{
    case "tl": //Top Left
        $startwidth     = 20;
        $startheight    = 20;
        break;
    case "bl": //Bottom Left
        $startwidth     = 20;
        $startheight    = (($imageheight - $watermarkheight) - 20);
        break;
    case "tr": //Top Right
        $startwidth     = (($imagewidth - $watermarkwidth) - 20);
        $startheight    = 20;
        break;
    case "br": //Bottom Right
        $startwidth     = (($imagewidth - $watermarkwidth) - 20);
        $startheight    = (($imageheight - $watermarkheight) - 20);
        break;
    case "middle": //Middle/center
        $startwidth     = (($imagewidth - $watermarkwidth) / 2);
        $startheight    = (($imageheight - $watermarkheight) / 2);
        break;
    case "repeat":
        // not sure what to do here
        break;
    default:
        $startwidth     = (($imagewidth - $watermarkwidth) / 2);
        $startheight    = (($imageheight - $watermarkheight) / 2);
}

imagecopymerge_alpha($image, $watermark,  $startwidth, $startheight, 0, 0, $watermarkwidth, $watermarkheight,$settings['watermark_opacity']);
imagejpeg($image,NULL,90);
imagedestroy($image);
imagedestroy($watermark);

How about posting your code. Just a guess, but that might help. — Paul Dessert, Feb 13 '12 at 23:12
We absolutely positively need to see the code you are already using so we can give you suggestions on how to make the watermark repeat. — Charles, Feb 13 '12 at 23:20
posted a pastie..its a ton of code..just focus on the switch case about 70 lines down — Ronnie, Feb 13 '12 at 23:21
It's not nearly as much code as you think it is. I've in-lined the relevant parts. — Charles, Feb 13 '12 at 23:31
I found my answer here: http://stackoverflow.com/questions/7333077/how-can-i-repeat-a-watermark-throughout-a-requested-image-using-php — Ronnie, Feb 13 '12 at 23:51
Here is some solution. This was found in this forum. http://stackoverflow.com/a/7379487/2345900 [1]: http://stackoverflow.com/a/7379487/2345900 — Sajitha Rathnayake, Apr 30 '14 at 12:04
this link can help you https://stackoverflow.com/questions/32005595/how-do-i-to-make-watermark-image-with-php-and-gd-like-envato-photodune-preview-i — mohamad mazaheri, May 07 '21 at 20:53
this link can help you https://stackoverflow.com/questions/32005595/how-do-i-to-make-watermark-image-with-php-and-gd-like-envato-photodune-preview-i — mohamad mazaheri, May 07 '21 at 20:54

score 2 · Answer 1 · answered Feb 13 '12 at 23:21

2

I don't entirely know how your script works, but can't you just repeat adding watermarks at fixed intervals until you have covered the entire width of the image?

answered Feb 13 '12 at 23:21

Amish Programmer

2,051
3
19
22

that doesn't seem too efficient, but it is an option I suppose – Ronnie Feb 13 '12 at 23:23

score 1 · Answer 2 · answered Mar 17 '12 at 08:09

1

I think the imagesettile function could help:

http://php.net/manual/en/function.imagesettile.php

Look at the example on that page.

answered Mar 17 '12 at 08:09

Anton Dieterle

656
8
8

How do I repeat a watermark image with GD and PHP?

2 Answers2