Customizable PHP thumbnail generator requires GD library support

The classic PHP thumbnail generation program, based on the GD library, can specify the generation path and the width and height details of the generation target. How to use: In a PHP environment that supports the GD library, save the following code as resize.php for testing
Classic PHP thumbnail The generation program, based on the GD library, can specify the generation path and the width and height details of the generation target
Usage: In a PHP environment that supports the GD library, save the following code as resize.php for testing

Copy the code The code is as follows :

$FILENAME="image_name";
//The width of the generated image
$RESIZEWIDTH=400;
//The height of the generated image
$RESIZEHEIGHT=400;
//The path of the generated image
$ uploaddir="c:/winnt/temp";
function ResizeImage($im,$maxwidth,$maxheight,$name){
global $uploaddir;
$width = imagesx($im);
$height = imagesy($ im);
if(($maxwidth && $width > $maxwidth) || ($maxheight && $height > $maxheight)){
if($maxwidth && $width > $maxwidth){
$widthratio = $maxwidth/$width;
$RESIZEWIDTH=true;
}
if($maxheight && $height > $maxheight){
$heightratio = $maxheight/$height;
$RESIZEHEIGHT=true;
}
if($ RESIZEWIDTH && $RESIZEHEIGHT){
if($widthratio < $heightratio){
$ratio = $widthratio;
}else{
$ratio = $heightratio;
}
}elseif($RESIZEWIDTH){
$ratio = $ widthratio;
}elseif($RESIZEHEIGHT){
$ratio = $heightratio;
}
$newwidth = $width * $ratio;
$newheight = $height * $ratio;
if(function_exists("imagecopyresampled")){
$newim = imagecreatetruecolor($newwidth, $newheight);
imagecopyresampled($newim, $im, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
}else{
$newim = imagecreate($newwidth, $newheight);
imagecopyresized($newim, $im, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);
}
ImageJpeg ($newim,$uploaddir .$name . ".jpg");
ImageDestroy ($newim);
}else{
ImageJpeg ($im,$uploaddir.$name . ".jpg");
}
}
if($_FILES[' image']['size']){
if($_FILES['image']['type'] == "image/pjpeg"){
$im = imagecreatefromjpeg($_FILES['image']['tmp_name ']);
}elseif($_FILES['image']['type'] == "image/x-png"){
$im = imagecreatefrompng($_FILES['image']['tmp_name']) ;
}elseif($_FILES['image']['type'] == "image/gif"){
$im = imagecreatefromgif($_FILES['image']['tmp_name']);
}
if ($im){
if(file_exists("$FILENAME.jpg")){
unlink("$FILENAME.jpg");
}
ResizeImage($im,$RESIZEWIDTH,$RESIZEHEIGHT,$FILENAME);
ImageDestroy ($im);
}
}
?>

The above has introduced the customizable PHP thumbnail generation program that requires the support of the GD library, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.