Adding watermarks to images using alpha channels

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- Adding watermarks to images using alpha channels

## Adding watermarks to images using alpha channels

Example #1 Adding watermarks to images using alpha channels

    <?php// Load the stamp and the photo to apply the watermark to$stamp = imagecreatefrompng('stamp.png');$im = imagecreatefromjpeg('photo.jpeg');// Set the margins for the stamp and get the height/width of the stamp image$marge_right = 10;$marge_bottom = 10;$sx = imagesx($stamp);$sy = imagesy($stamp);// Copy the stamp image onto our photo using the margin offsets and the photo // width to calculate positioning of the stamp. imagecopy($im, $stamp, imagesx($im) - $sx - $marge_right, imagesy($im) - $sy - $marge_bottom, 0, 0, imagesx($stamp), imagesy($stamp));// Output and free memoryheader('Content-type: image/png');imagepng($im);imagedestroy($im);?>

This example is a common way to add watermarks and stamps to photos and copyrighted images. Note that the presence of an alpha channel in the stamp image as the text is anti-aliased. This is preserved during copying.