public function register()
    {
        return add_image_size(
            $this->getSlug(),
            $this->getArgument('size')[0],
            $this->getArgument('size')[1],
            $this->getArgument('crop')
        );
    }
public function register()
    {
        return add_image_size(
            $this->getSlug(),
            $this->getArgument('size')[0],
            $this->getArgument('size')[1],
            $this->getArgument('crop')
        );
    }
public function register ( ) { return add_image_size ( $ this -> getSlug ( ) , $ this -> getArgument ( 'size' ) [ 0 ] , $ this -> getArgument ( 'size' ) [ 1 ] , $ this -> getArgument ( 'crop' ) ) ; }
Register thumbnail size.

@return void
Register thumbnail size .