GD/Imagick doesn't save my image
===

I want to send an image from android and save it trought a php code in my server. Because I need to protect my server I need to reprocess the image so I have to use GD or Imagick. Image is sent encoded in base64. In the php file is decoded and if I use:

    $img=base64_decode($img);
    $file = fopen('test.jpg', 'wb');
    fwrite($file, $img);
    fclose($file);

image is saved in the server. If I use Imagick or GD my image isn't saved and the php files returns nothing, even if I insert an echo after it. Any help? In GD I was using:
		
    $img=base64_decode($img);
    $imageinfo = getimagesize($img);
    if($imageinfo['mime'] == 'image/gif'{
	    $img = @imagecreatefromjpeg($img);
	    imagejpeg($img, ""testt.jpg", 80);
    }

and in Imagick:

    $img=base64_decode($img);
    $img = imagick($img); //neither if I use a path of an image saved in my server 
                          //works
    $mime = mime_content_type($img);
		switch ($mime):
			case 'image/jpeg':
				$ext = '.jpg';
				break;
		endswitch;

    $img->stripImage();
    $img->writeImage(""testt".$ext);
    $img->clear();
    $img->destroy();