LifeType 中文開發論壇

list($width, $height) = getimagesize($image_file);
$img_ratio = $width / $height; // Obtain the image ratio
$thumbnail_dimension = 100; // or any other value you like
if ($width >= $height) {
	//Landscape Image
	if ($width > $thumbnail_dimension) {
		$new_width = $thumbnail_dimension;
		$new_height = round($new_width / $img_ratio);
	} else {
		$new_width = $width;
		$new_height = $height;
	}
} else {
	//Portrait Image
	if ($height > $thumbnail_dimension) {
		$new_height = $thumbnail_dimension;
		$new_width = round($new_height * $img_ratio);
	} else {
		$new_width = $width;
		$new_height = $height;
		}
	}
// .... resize picture