Hi, I’m trying to create a thumbnail image based on an image uploaded via the form and so far I have got this working all well.
My issue is that I don’t want to define the width and height of the thumbnail through the php file, instead this should resize based on a height and width field values in the database.
above the code where it creates the image I have made a database query and assigned these two values to :
$the_thumb_width and $the_thumb_height
When I replace the static values in the file with the variables, I get an error and the file is not created. The error is:
Warning: imagecreatetruecolor() [function.imagecreatetruecolor]: Invalid image dimensions in /web/…
I echo’d out the variables to test if they are being pulled in and they are, so I don’t understand why this is occurring. Can anyone help? I’m pasting the area of the code that generates the thumbnail. Thanks! 
[php]
//-------------------- create thumbnail --------------------------------------------
function createthumb($src_filename, $dst_filename_thumb)
{
$size = getimagesize($src_filename);
$stype = $size[‘mime’];
$w = $size[0];
$h = $size[1];
switch($stype) {
case ‘image/gif’:
$simg = imagecreatefromgif($src_filename);
//header(“Content-type: image/gif”);
break;
case ‘image/jpeg’:
$simg = imagecreatefromjpeg($src_filename);
//header(“Content-type: image/jpg”);
break;
case ‘image/png’:
$simg = imagecreatefrompng($src_filename);
//header(“Content-type: image/png”);
break;
}
// get image width
$width = $w;
// get image height
$height = $h;
// size to create thumnail width
$thumb_width = $the_thumb_width;
$thumb_height = $the_thumb_width;
$dimg = imagecreatetruecolor($thumb_width, $thumb_height);
$wm = $width/$thumb_width;
$hm = $height/$thumb_height;
$h_height = $thumb_height/2;
$w_height = $thumb_width/2;
if($w> $h) {
$adjusted_width = $w / $hm;
$half_width = $adjusted_width / 2;
$int_width = $half_width - $w_height;
imagecopyresampled($dimg,$simg,-$int_width,0,0,0,$adjusted_width,$thumb_height,$w,$h);
} elseif(($w <$h) || ($w == $h)) {
$adjusted_height = $h / $wm;
$half_height = $adjusted_height / 2;
$int_height = $half_height - $h_height;
imagecopyresampled($dimg,$simg,0,-$int_height,0,0,$thumb_width,$adjusted_height,$w,$h);
} else {
imagecopyresampled($dimg,$simg,0,0,0,0,$thumb_width,$thumb_height,$w,$h);
}
$ran = "thumb_".rand () ;
global $thumb2;
$thumb2 = $ran.".jpg";
global $thumb_Add_thumb;
$thumb_Add_thumb = $dst_filename_thumb;
$thumb_Add_thumb .= $thumb2;
imagejpeg($dimg, "" .$dst_filename_thumb. "$thumb2");
[/php]