Image Create From PNG

Hi, I am trying to learn php and when I feel i understand a concept I like to try it out by writing a script or two. I am currently attempting to create an image on the fly, like a button. I kept receiving the message:
Warning: imagecreatefrompng(red-button.png) [function.imagecreatefrompng]: failed to open stream: No such file or directory.
But the error was gone when I commented a few lines to check then removed it ,pls check in your editor most probably -line no. 15 and line no. 43 and added the line 44:header("content-type:image/png.jpeg.");

But then I started getting the following error :
Parse error: syntax error, unexpected T_CONSTANT_ENCAPSED_STRING in c:\xampp\htdocs\web\button\make_button.php on line 21

Could someone please take a look at this for me and tell me what you think I've done wrong?? I would really appreciate it, I've looked at it until my eyes have about gone on strike. Here is the full code:

HTML Code:

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<form name ="button" action ="make_button.php" method="post">
<input type ="text" name = "button_text">
 
<p>
<label>
<input type="radio" name="color" value="red" id="red">
Red</label>
 
<label>
<input type="radio" name="color" value="green" id="green">
Green</label>
 
<input type="radio" name="color" id="blue" value="blue">
Blue</label>
</p>
 
<input type ="submit" name ="submit" value ="CREATE!">
</form>
 
<?php
$button_text=$_POST['button_text'];
$color=$_POST['color'];
 
if(empty($button_text)||empty($color))
{
echo 'Could not create image - form not filled out correctly';
exit;
}
 
$im=imagecreatefrompng('\button'.$color.'-button.png');
 
$width_image=imagesx($im);
$height_image=imagesx($im);
 
$width_image_wo_margins=$width_image-(2*18);
$height_image_wo_margins=$height_image-(2*18);
 
$font_size=33;
 
//putenv('GDFONTPATH=C:\WINDOWS\Fonts');
$fontname='arial';
do
{
        $font_size--;
 
        $bbox=imagettfbbox($font_size,0,$fontname,$button_text);
        $right_text=$bbox[2];
        $left_text=$bbox[0];
        $width_text=$right_text - $left_text;
        $height_text=abs($bbox[7]-$bbox[1]);
}
while($font_size>8 && ($height_text>$height_image_wo_margins||$widht_text>$width_image_wo_margins));
if($height_text>$height_image_wo_margins||$widht_text>$width_image_wo_margins)
{
        echo 'Text given will not fit on button.<br>';
}
else
{
        $text_x=$width_image/2.0-$width_text/2.0;
        $text_y=$height_image/2.0-$height_text/2.0;
 
        if($left_text<0)
                $text_x+=abs($left_text);
        $above_line_text=abs($bbox[7]);
$text_y +=$above_line_text;
$text_y -=2;
$white=imagecolorallocate($im,255,255,255);
imagettftext($im,$font_size,0,$text_x,$text_y,$white,$fontname,$button_text);
//header('Content-type:image/png');
header("content-type:image/png.jpeg.");
 
imagepng($im);
}
imagedestroy($im);
?>

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I am getting the error from this line -

HTML Code:

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putenv('GDFONTPATH=C:\WINDOWS\Fonts'); 

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