(I am not sure if that the right forum but I didn't see any other forums that would cover this topic but if it the wrong forum please move it to the correct forum moderator. Thank you)
Mplayers always had supported the pop-on (pops on screen and disppears) closed captions using -subcc switch but not the roll-on (scrolling from bottom to upward) closed caption since those type of captions are not normally found on DVDs.
Some tv tuner cards with latest driver are now saving Closed Captions into mpeg file similar to DVD closed caption so mplayer are able to read and display those closed caption however it would not display the roll-on type of closed caption normally seen on live broadcast or educated shows or soap shows.
I am traveling a lot and being deaf I wanted to take my recorded show with me on my laptop but could never find a player that could play back the show with roll-on caption either via harddrive or network until I was able to find someone to patch mplayer to support it.
You can download complied Windows Mplayer at http://www.findmall.com/cc-mplayer.zip
or use the change diff attached to this post if you complie your own mplayer.
There is no need to extract or covert the closed caption to subtitles unless your tv tuner card does not save or support CC into mpeg file similar to DVD closed captions.
Docs on using mplayer can be found at http://www.mplayerhq.hu/design7/info.html#docs