public function setOptions($options = array())
    {
        $default = array(
            "characterSet" => 'two',
            "scale" => 14,
            "luminanceStrategy" => 3,
            "customCharacterSet" => null,
        );
        $default = array_merge($default, $options);
        
        if (!is_null($default['customCharacterSet'])) {
            $this->addCharacterSet('custom', $default['customCharacterSet']);
            $default['characterSet'] = 'custom';
        }
        
        $this->scale = $default['scale'];
        $this->characters = $this->characterSet[$default['characterSet']];
        $this->charCount = strlen($this->characters);
        $this->luminanceStrategy = $default['luminanceStrategy'];
        
        return $this;
    }