public function convert(string $file, Conversion $conversion = null) : string
{
$imageFile = pathinfo($file, PATHINFO_DIRNAME) . '/' . pathinfo($file, PATHINFO_FILENAME) . '.jpg';
$image = new \Imagick();
$image->readImage($file);
$image->setBackgroundColor(new ImagickPixel('none'));
$image->setImageFormat('jpg');
file_put_contents($imageFile, $image);
return $imageFile;
}