php support the GD Graphic, with this you can display the image on run time, you can genrate the png/gif file with php
PHP Code:
<?php
header("Content-type: image/png");
$string = 'Any Text';
$im = imagecreatefrompng("images/button1.png");
$orange = imagecolorallocate($im, 220, 210, 60);
$px = (imagesx($im) - 7.5 * strlen($string)) / 2;
imagestring($im, 3, $px, 9, $string, $orange);
imagepng($im);
imagedestroy($im);
?>
Regards
Jitender