[mythtv] Teletext idea/question

Navaho Gunleg navahogunleg at gmail.com
Wed May 10 10:00:30 UTC 2006

    Hi there, fellow enthusiasts!

First up: I have looked at some of the code, played around with it to
get acquainted with MythTVs architecture and I have to say you all
have been doing a mighty fine job. ;)

Let me share an idea that I got, to discuss its feasability and hear
with you think. Let me explain what 'inspired' me first.

I'm Dutch, and I watched the BBC with MythTV the other day. As I do
speak English, I still like to use the teletext-supplied subtitles on
teletext/cc page 888, just in case I don't hear a word correctly. When
doing this, I noticed there is a slight timing problem: the subtitles
appear just a wee bit too soon (about 1/2 second).

Later, when watching a 'live' BBC programme where the subtitles are
typed live by a person, I noticed that, although on the usual TV these
'live-typed' subtitles are always late, that the subtitles came up
just as the people spoke -- as good as in-sync!

It would be interesting to know where this 'bug' comes from, because
this timing 'issue' could be used to its advantage. (This isn't a bug,
it's a feature ;)) It would be nice if this delay could be
configurable (although within certain limits -- a delay of more than a
few minutes is silly). Or am I the only guy that finds those
live-typed subtitles, that miserably fail to keep up with the speaker,
annoying? ;)

Now I understand that this probably isn't as easy a task to accomplish
as it sounds and neither do I really understand how the teletext pages
are sent to the frontend. I do understand its encapsulated in the MPEG
stream somehow, which would make it troublesome to 'timeshift' the
teletext relative to the audio and video data on the frontend itself.
If someone 'in-the-know' could shed some light on this and/or give
some pointers, I'd be really grateful.

Cheers and keep up the good work!

More information about the mythtv-dev mailing list