text: #ifdef USE_MPEGLIB
  extern void VideoDevice_preview_init(GtkWidget* main_window, GtkWidget* winManager);
  extern void VideoDevice_shutdown();
  extern void Player_start();
  extern void Player_stop();
  extern void Video_start();
  extern void Video_stop();
  #else
  #define  VideDevice_preview_init(main_window, winManager) 
  #define  VideoDevice_shutdown()
  #endif
  