Demuxer tty [Tele-typewriter]:
    Common extensions: ans,art,asc,diz,ice,nfo,txt,vt.
TTY demuxer AVOptions:
  -chars_per_frame   <int>        .D....  (from 1 to INT_MAX)
  -video_size        <image_size> .D.... A string describing frame size, such as 640x480 or hd720.
  -framerate         <video_rate> .D.... 

