The program is x264 and it can be interactive to some extent--it has a "reconfig" function that allows you to reconfigure the parameters on the fly, though it h

The program is x264 and it can be interactive to some extent--it has a "reconfig" function that allows you to reconfigure the parameters on the fly, though it has some limitations as to what you can adjust and what you cannot. One potential purpose of this is a "speed control" feature where you adjust settings on the fly to ensure realtime operation, such as for a broadcast encoding server (my company does this).