PicHandler, resize images on the fly

pic.php

<?
	if(!isset($_GET['img'])) die('No URL image given');
	$image = getimagesize($_GET['img']);
	$qlty = isset($_GET['cqlty']) ? ($_GET['cqlty'] <= 100 ? $_GET['cqlty'] : 80) : 80;
	if ($image === false) die;
	$mime = explode('/', $image['mime']);
	$ext = $mime[1];

	switch($ext){
		case('jpg'): case('jpeg'): case('jpe'):
			$buffer = imagecreatefromjpeg($_GET['img']);
		break;
		case('png'):
			$buffer = imagecreatefrompng($_GET['img']);
			$qlty = ($qlty * 0.1 == 10) ? 9 : ceil($qlty * 0.1);
		break;
		case('gif'):
			$buffer = imagecreatefromgif($_GET['img']);
		break;
		default:
			return false;
		break;
	}

	$width  = $image[0];
	$height = $image[1];

	if(isset($_GET['cwidth'])){
		$new_width = $_GET['cwidth'];
		$new_height = !isset($_GET['cheight']) ? $height * ($new_width/$width) : $_GET['cheight'];
	}
	if(isset($_GET['cheight'])){
		$new_height = $_GET['cheight'];
		$new_width = !isset($_GET['cwidth']) ? $width * ($new_height/$height) : $_GET['cwidth'];
	}

	if(isset($_GET['cheight']) || isset($_GET['cwidth'])){
		$function = 'image'.$ext;		
		if(isset($_GET['cut'])){
			if(isset($_GET['cwidth'])){
				$image_resized = imagecreatetruecolor($_GET['cwidth'], ($new_height < $_GET['cwidth'] ? $new_height : $_GET['cwidth']));
			}
			if(isset($_GET['cheight'])){
				$image_resized = imagecreatetruecolor($new_width, ($new_width > $_GET['cheight'] ? $new_width : $_GET['cheight']));
			}
		}
		else $image_resized = imagecreatetruecolor($new_width, $new_height);
		imagealphablending($image_resized, false);
		if(isset($_GET['cut']) && isset($_GET['cheight'])) imagecopyresampled($image_resized, $buffer, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
		else imagecopyresampled($image_resized, $buffer, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
		//ImageAlphaBlending($image_resized, true);
		imagesavealpha($image_resized, true);

		header('Content-type: '.$image['mime']);
		if($ext == 'gif') $function($image_resized);
		else $function($image_resized, null, $qlty);
		imagedestroy($buffer);
		imagedestroy($image_resized);
	}
?>