[linux-dvb] Re: saa7146 and teletext (vbi)

["Karsten Kreyenburg" <karsten.kreyenburg@wunstorf-luthe.de>]

I absolutely understand that there is no vbi information muxed into the
video PID or whatever.

I think that the vbi information is on a separate Teletext-PID. I think that
dvbtext is already an application which accesses this information. But it
would be nice to have it redirected into a vbi device (like /dev/vbi0), so
common (analog) Teletext applications could access it.

The reason is, that I would like to run Nextview EPG:
http://nxtvepg.sourceforge.net/intro.html

From the description:
"...,if you have an internal SAT TV card, a Linux driver which supports the
video4linux VBI API (i.e. if other VBI applications like alevt work too.)"

You might have discovered that RTL World (RTL, RTL2, VOX, Super RTL) doesn't
provide much EPG data on their channel. In fact you only get the name of the
actual running movie. With Nextview, you could access the teletext
information on "Kabel 1", which seems to contain a complete electronic TV
programme guide also covering RTL Worlds stations. Furthermore, Nextview can
export the received information into the xmltv format.

That would be a very reliable (and legal!) way to obtain an electronic TV
programme guide.

> -----Ursprüngliche Nachricht-----
> Von: linux-dvb-bounce@linuxtv.org
> [mailto:linux-dvb-bounce@linuxtv.org]Im Auftrag von Robert Schlabbach
> Gesendet: Sonntag, 20. Juni 2004 14:36
> An: linux-dvb@linuxtv.org
> Betreff: [linux-dvb] Re: saa7146 and teletext (vbi)
>
>
> I'm not sure if you're aware of this, but there is no VBI in digital
> television. There is a way to encapsulate the VBI _data_ in a DVB stream,
> see ETSI EN 301 775 and ETSI EN 300 472.
>
> But that VBI data must be filtered by the MPEG-2 demultiplexer,
> and I'm not
> sure if the Linux MPEG-2 demux is actually providing /devs for the PIDs it
> filters?
>
> So if you were looking for a way to connect a "waveform decoder"
> to a "raw"
> VBI output, that's not the way DVB works. You already get the decoded
> waveforms (i.e. the decoded Teletext lines) in the data stream,
> and all you
> have to do is retrieve that data and directly feed it into a Teletext
> "renderer".
>
> FWIW, you can also get VPS and WSS from some German DVB services.
>
> Regards,
> --
> Robert Schlabbach
> e-mail: robert_s@gmx.net
> Berlin, Germany
>
>