无法旋转.png图像：错误“除以零”

Question

我在php中处理图像处理，目前我正在尝试使用php旋转图像（比如在给定角度旋转图像）。 jpg和jpeg图片上的所有内容都很顺利，但是在png图像中失败了。

它会抛出错误：division by zero。

如果任何人都有很好的想法在GD库中旋转png图像;建议我仅用于GD库。我不能在想象中工作。

$file_ext = preg_split("/\./",$image_name);
$filetype = end($file_ext);
switch($filetype){
    case "gif":
        $source = imagecreatefromgif($file);
        list($width, $height, $type, $attr) = getimagesize($file);
    break;
    case "jpg":
        $source = imagecreatefromjpeg($file);
        list($width, $height, $type, $attr) = getimagesize($file);
    break;
    case "jpeg":
        $source = imagecreatefromjpeg($file);
        list($width, $height, $type, $attr) = getimagesize($file);
    break;
    case "png":
//  echo 'asdasd';
        $source = imagecreatefrompng($file);
        //imagealphablending($source, FALSE);
        //imagesavealpha($source, TRUE);
        list($width, $height, $type, $attr) = getimagesize($file);
    break;
}

//echo $width; die;
$tempImg = imagecreatetruecolor($width, $height) or die("Cant create temp image");
imagecopyresized($tempImg, $source, 0, 0, 0, 0, $width, $height, $width, $height) or die("Cant resize copy");
$rotate = imagerotate($source,$angle,imageColorAllocateAlpha($source, 255, 255, 255, 127));

switch($filetype){
    case "gif":
        @imagegif( $rotate,USER_CROP_FOLDER.$image_name,90);
    break;
    case "jpg":
        @imagejpeg( $rotate,USER_CROP_FOLDER.$image_name,90);
    break;
    case "jpeg":
        @imagejpeg( $rotate,USER_CROP_FOLDER.$image_name,90);
    break;
    case "png":
        imagealphablending($rotate, FALSE);
        imagesavealpha($rotate, TRUE);
        @imagepng( $rotate,USER_CROP_FOLDER.$image_name,90);
    break;
}