Image quality problems

[dan744]

I'm trying to modify an image using php and GD to basically add a copyright at the bottom when somebody views it.
The idea is to take the original image, add a balck line at the bottom with the white lettering stating the copyright. At the moment it is working great except that it seems the orignial image (a jpg photo) has lost a lot of quality, it looks like its converting it to 255 colours as the colours are all wrong.

Is there a way around this? The server I'm on has GD 1.6 which is pretty old, the only things I've read that might work are functions where version 2.0 or higher is required.
I've asked my hosting company about upgrading but not had a response yet, is there anything that might work in the meantime?

Heres the code:

<?


$pathmain3 = "/usr/local/customer/virtualfp/www.plane-mad.com/photos/$filename.jpg";

$pathmain1 = ImageCreatefromjpeg($pathmain3);
$pathmain4 = "/usr/local/customer/virtualfp/www.plane-mad.com/pictures/pmsm.jpg";
$pathmain2 = ImageCreateFromJPEG($pathmain4);

$height = imagesy($pathmain1);
$width = imagesx($pathmain1);
$string_width2 = 170;
$start = $width-$string_width2; 
$heighttotal = $height+15;

$img = ImageCreate($width,$heighttotal); 

$black = ImageColorAllocate($img, 0, 0, 0); $white = ImageColorAllocate($img, 255, 255, 

255);

$photoinfo = "MyTravel Lite A320 @ Birmingham";
$info = "Photo Copyright Danny Hill | $photoinfo"; 

ImageFill($img, 0, 0, $black);
ImageString($img, 3, 3, $height, "$info", $white);
imagecopy ($img, $pathmain2, $start, $height, 0, 0, $width, 15);


imagecopy($img, $pathmain1, 0, 0, 0, 0, $width, $height);

Header( "Content-type: image/jpeg"); 
ImageJPEG($img,'',99); 

ImageDestroy($pathmain1); 
ImageDestroy($img); 
ImageDestroy($pathmain2); 
?>

The original image: http://www.plane-mad.com/photos/vz320_bhx-7.jpg

The resulting image: http://www.plane-mad.com/photo_copy.php?filename=vz320_bhx-7

The problem is worse on the grass underneath the aircraft.

Any help would be appreciated.

[bobthedog]

I think I've come across this problem before, and ended up with a problem which I think was linked to the fact that the colours i was using weren't in the original images colour pallette. Therefore, it was stealing other colours to make the colours i wanted which was affecting the look of the rest of the image. I know this isn't the way it should work - but the only way i resolved it was to ensure the colours i was adding were already in the images colour pallette.

This is just a thought though - otherwise, maybe try updating to latest version of GD??

[dan744]

Thanks for the idea.

The only colours I'm using that aren't in the main jpg photo are pure white (255, 255, 255) and pure black (0, 0, 0).
I tried replacing ImageColorallocate with ImageColorclosest using the jpg file but still have the problem, the resulting black is black but the white is now way off, to add another problem.

Think I'll try upgading GD, but that may have to be done by the hosting company, who I'm awaiting an answer from!

Thanks anyway.