prova:
function resizeimage($resource,$size){
//RIDIMENSIONO CON LE GD
$tmpimage=imagecreatefromstring($resource);
$src_width=imagesx($tmpimage);
$src_height=imagesy($tmpimage);
$ratio=$src_height / $size;
$tmp_resized=imagecreatetruecolor($src_width / $ratio,$src_height / $ratio);
imagecopyresampled($tmp_resized, $tmpimage, 0, 0, 0, 0,
$src_width / $ratio,
$src_height / $ratio,
$src_width,
$src_height);
imagedestroy($tmpimage);
return imagejpeg($tmp_resized);
}
$query="select image from tabella where id=$id";
$result=mysql_query($query) or die("caricamento immagine non riuscito");
$oggetto=mysql_fetch_array($result);
$resource=$oggetto['image'];
resizeimage($resource,80);