Save an XBM file with a different foreground color in PHP

<?php/*from w w  w .j  av  a  2  s  .  co  m*/
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5,  'A Simple Text String', $text_color);

// Set a replacement foreground color
$foreground_color = imagecolorallocate($im, 255, 0, 0);

// Save the image
imagexbm($im, NULL, $foreground_color);

// Free up memory
imagedestroy($im);
?>