[mythtv-users] VBI subtitles with ivtv cards?

[Jesse Guardiani]

Mark Cooke wrote:

[...]

>>> Hans did state a long term goal of providing standards-based VBI data in
>>> the IVTV stream on the IVTV list (or maybe the V4l list) not too long
>>> ago.
>>>   
>>>       
>> Yes. That's why I keep trying to find spec information on what a 
>> "standard" VBI stream looks like.
>> But I'm not an mpeg/hardware programmer and so far simply asking around 
>> hasn't turned up anything.
>>     
>
> Well, the specs for this are all freely available...
>
> ESTI Docs (register with just an email address for as many downloads of
> ESTI specs as you want.  They've sent me 1 email invite to a conference
> since I registered 6 weeks ago, so it's not a major spam-source):
>
> EN 300 294 : TV WSS 625-line (PAL) spec. (v 1.4.1)
> EN 300 429 : DVB framing structure/coding/modulation
> EN 300 468 : Service Information spec (1.6.1)
> EN 300 472 : ITU-R Teletext in DVB bitstreams (1.3.1)
> EN 300 706 : Enhanced Teletext spec (1.2.1)
> EN 301 775 : VBI information in DVB bitstreams (1.1.1)
>              (WSS / CC / teletext / vps )
>
> TR 101 211 : SI guidelines  (1.6.1)
> TS 101 154 : Implementation guidelines (1.7.1)
> TS 101 197 : Head-end architecture (1.2.1)
>
> The 472 and 775 specs are the most handy for the VBI stuff, but I
> haven't had sufficient time to read them in enough detail to hack up
> ivtv-vbi.c to do 'standards-based' encoding.
>   


Thanks! That's great information, but I don't think it quite answers the 
original question:

How does MythTV currently expect VBI data from other drivers to be encoded?
In other words, does MythTV treat each driver individually? Or does MythTV
have a certain VBI format standard or standards it expects?

If it's just one standard, and we can put a name to it, then ivtv can 
probably be
modified accordingly. But if each driver is treated specially, then I 
guess it's just
a matter of getting ivtv specific VBI support added to MythTV, right?

Thanks again!


-- 
Jesse Guardiani
Programmer/Sys Admin
jesse at wingnet.net