Как снять лимит в GD PHP?

<?php
session_start();
ini_set("memory_limit","128M");
 
$SIZE = 128;
$M_WIDTH = 32*2;
$M_HEIGHT = 18*2;
 
$WIDTH = $M_WIDTH*$SIZE;
$HEIGHT = $M_HEIGHT*$SIZE;
 
header("Content-Type: image/png");
 
$image = imagecreatetruecolor($WIDTH,$HEIGHT);
imagefill($image,0,0,0);
 
$white = imagecolorallocate($image,255,255,255);
$red = imagecolorallocate($image,200,40,40);
$green = imagecolorallocate($image,40,200,40);
$blue = imagecolorallocate($image,40,40,200);
$yellow = imagecolorallocate($image,200,200,40);
 
imagettftext($image,16,5,2,30,imagecolorallocate($image,255,255,255),"Arial.ttf",strtotime('now'));
 
$CENTER_X = $WIDTH/2;
$CENTER_Y = $HEIGHT/2;
 
for($i = 0, $a = 1, $c = 1, $x = $CENTER_X, $y = $SIZE*2, $nx = 1, $ny = 1; $y <= $HEIGHT-$SIZE; $i+=$a)
{
    while($x <= $CENTER_X+$SIZE*$i)
    {
        if($c == count($colors)-1) $c = 1;
        else $c++;
        
        $points = array($x,$y+$SIZE/2,$x-$SIZE,$y,$x,$y-$SIZE/2,$x+$SIZE,$y);
        
        imagepolygon($image,$points,4,$green);
        
        $x+=$SIZE*2;
        $nx++;
    }
    
    if($x > $CENTER_X-$SIZE*$i-$SIZE)
    {
        if($CENTER_X-$SIZE*($i+1) <= 0) $a = -1;
        $x = $CENTER_X-$SIZE*($i+$a);
        $y+=$SIZE/2;
        $nx = 1;
    }
    
    $ny+=2;
}
 
imagepng($image);
?>

#!/usr/bin/php -d memory_limit=1G
<?php
// ...

<?php $img = imagecreatefrompng("bgs/bg{$_GET[id]}.png"); ?>