Typo3 7.6.xx - Croping a Image via PHP cObject Configuration

function getImage($file,$width,$height){
$imgConf = array();
$imgConf['file'] = $file;
$imgConf['file.']['width'] = $width.'c';
$imgConf['file.']['height'] = $height.'c';
return $this->cObj->Image($imgConf);
}