How to add rotang to image.php

Question

add this

$rotang = 20; // Rotation angle

to

<?php
    $img = imagecreatefrompng("img.png");
    $textcolor = imagecolorallocate($img,205,205,205);
    $number1= " Your IP is $_SERVER[REMOTE_ADDR]";
    $number2= " Today is " . date("Y/m/d") ;
    imagestring($img,10,5,5,$number1,$textcolor);
    imagestring($img,10,5,30,$number2,$textcolor);
    header("Content-type: image/png");
    imagepng($img);
    imagedestroy($img);
?>

i want to the output is completely php

sample output image enter image description here