Transparency not preserved after applying imagecopyresampled

Question

I have a question related to the GD library on PHP. I can't add a transparent image to the canvas in a way that preserves the transparency.

Here is the output that I get

Here is the code that I used

$canvas = imagecreatetruecolor(4000, 4000);
imagealphablending($canvas, false);
imagesavealpha($canvas, true);
$color = imagecolorallocatealpha($canvas, 255, 250, 156, 0);
imagefill($canvas, 0, 0, $color);

$mask = imagecreatefrompng('mask.png');
imagealphablending($mask, false);
imagesavealpha($mask, true);

imagecopyresampled($canvas, $mask, 500, 500, 0, 0, 1500, 1500, imagesx($mask), imagesy($mask));

header("Content-type: image/png");
imagepng($canvas);
exit;

As you can see, the image with the dog has a white background, but I need a yellow background (like on the canvas) instead of this white background.

Please write what is my mistake. Thank you very much.

You'd need to provide the input images separately if you wanted some assistance. — Mark Setchell, Mar 27 '23 at 07:01
Need to call `imagealphablending` and `imagesavealpha` on the target `$canvas`. [See this previous answer](https://stackoverflow.com/a/32302/21146235) for an example. — motto, Mar 27 '23 at 07:02
@motto hi. But I did it at the very beginning of the script. — Daniel Abyan, Mar 27 '23 at 07:26

score 0 · Answer 1 · answered Mar 29 '23 at 05:36

0

I found problems, I shouldn't have used this code

imagealphablending($canvas, false);
imagesavealpha($canvas, true);

Thx

answered Mar 29 '23 at 05:36

Daniel Abyan

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Transparency not preserved after applying imagecopyresampled

1 Answers1