/**
  * Constructor
  *
  * @access public
  * @author: Oliver Lillie
  * @param string $program The programme to call. Note this is not the path. If you wish to call ffmpeg/aconv you should jsut
  *  supply 'ffmpeg' and then set the aconv path as the ffmpeg configuration option in Config.   
  * @param PHPVideoToolkit\Config $config The config object.
  */
 public function __construct($programme, Config $config = null)
 {
     parent::__construct($programme, $config);
     $this->_progress_callbacks = array();
     $this->_output_renamed = null;
     $this->_final_output = null;
 }
 public function __construct($binary_path, $temp_directory)
 {
     parent::__construct($binary_path, $temp_directory);
     $this->_progress_callbacks = array();
 }