static function zoom($picture, $file_name = array('zoom_test.png', '../picture/zoom/'), $length, $is_height = false)
{
$image = palette::open($picture);
$start_width = palette::info($image, 'width');
$start_height = palette::info($image, 'height');
$end_width = $length;
$end_height = round($start_height * $end_width / $start_width);
if ($is_height) {
$end_width = round($start_width * $length / $start_height);
$end_height = $length;
}
$canvas = palette::create($end_width, $end_height, 'ffffff', true);
$param = array(0, 0, 0, 0, $end_width, $end_height, $start_width, $start_height);
palette::copy($canvas, $image, $param, 4);
palette::save($canvas, $file_name[0], $file_name[1]);
return $file_name[1] . $file_name[0];
}
