original_string: protected function leadMKV()
  	{
  		$lead = $this->ffprobeFormat("matroska", "webm");
  
  		if ($lead === true)
  		{
  			if ($this->ffprobeHasVideo() !== false)
  			{
  				return $this->closeCase("mkv", "video/x-matroska", $this->metadata);
  			}
  			else
  			{
  				return false;
  			}
  		}
  
  		return null;
  	}
code: protected function leadMKV()
  	{
  		$lead = $this->ffprobeFormat("matroska", "webm");
  
  		if ($lead === true)
  		{
  			if ($this->ffprobeHasVideo() !== false)
  			{
  				return $this->closeCase("mkv", "video/x-matroska", $this->metadata);
  			}
  			else
  			{
  				return false;
  			}
  		}
  
  		return null;
  	}
code_tokens: protected function leadMKV ( ) { $ lead = $ this -> ffprobeFormat ( "matroska" , "webm" ) ; if ( $ lead === true ) { if ( $ this -> ffprobeHasVideo ( ) !== false ) { return $ this -> closeCase ( "mkv" , "video/x-matroska" , $ this -> metadata ) ; } else { return false ; } } return null ; }
docstring: Checks if the file is a MKV.
  
  @return boolean|null
docstring_tokens: Checks if the file is a MKV .