public function format($format)
    {
        if (!$this->image) {
            $this->image();
        }

        $this->format = $format;

        return $this;
    }
public function format($format)
    {
        if (!$this->image) {
            $this->image();
        }

        $this->format = $format;

        return $this;
    }
public function format ( $ format ) { if ( ! $ this -> image ) { $ this -> image ( ) ; } $ this -> format = $ format ; return $ this ; }
Sets image output format.

@param string $format
@return $this
Sets image output format .