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Merging two images with transparencies in PHP

I am trying to make a composite image of several .png with background transparency via php and save the resulting image in my database. My problem is that the transparent sections of my images are deleted when the images are merged.

This is my code for creating a composite image:

    $base = imagecreatefrompng('application/assets/images/vel1_bg.png');
    imagealphablending($base, true);
    list($baseWidth, $baseHeight, $type, $attr) = getimagesize('application/assets/images/vel1_bg.png');

    $user_board_items = $this->config->item('user_board_items');

    foreach($array as $key => $value){
        $item = imagecreatefrompng('application/assets/images/items/' . $user_board_items[$value[0]] . '.png');         
        imagealphablending($item, true);
        list($width, $height, $type, $attr) = getimagesize('application/assets/images/items/'. $user_board_items[$value[0]] . '.png');

        imagecopymerge($base,
                    $item,
                    floor(($value[1] / 100) * $baseWidth),
                    floor(($value[2] / 100) * $baseHeight),
                    0,
                    0,
                    $width,
                    $height,
                    100);
        imagedestroy($item);
    }

    //We have to capture the output buffer
    ob_start();
    imagepng($base);
    $baseimg = ob_get_clean();

This creates an image similar to this: enter image description here

And I'm looking for something more like this: enter image description here (Note how transparent sections are displayed)

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2 answers

Do not use imagecopymerge () to merge a transparent image.

Better to use imagecopyresampled () in a script.

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, imagecopyresampled , . , , , . , :

  imagecopyresampled($base,
                $item,
                floor(($value[1] / 100) * $baseWidth),
                floor(($value[2] / 100) * $baseHeight),
                0,
                0,
                $width,
                $height,
                $width,
                $height);
0

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