Which audio-pid (and teletext subtitles :)

[boppen]

Hi!

Just a question - which audio-pid is selected when I tune to a channel with multiple languages? Some children channels have like four different languages, is it the "first" Audio-PID that's used? Some channels even have two languages on the same PID, Swedish on the right channel and Danish for example on the left. I know that VDR 1.3.32 handles this, it automaticly selects the right language if that is setup under Settings/DVB - but does that affect how the vompserver plugin handles audio?

And a little feature request that  maybe only interestinfg to Swedish users - teletext subtitles ...

[torsten]

Hi,

teletext is interesting too in germany, like in other PAL countries.

Probably one can use some code of the osdteletext-plugin of the vdr.

Torsten

[davep]

Hi!

Just a question - which audio-pid is selected when I tune to a channel with multiple languages? Some children channels have like four different languages, is it the "first" Audio-PID that's used? Some channels even have two languages on the same PID, Swedish on the right channel and Danish for example on the left. I know that VDR 1.3.32 handles this, it automaticly selects the right language if that is setup under Settings/DVB - but does that affect how the vompserver plugin handles audio?

At present the "first" audio PID is selected. Internationalisation is Work In Progress...

Dave

[Chris]

Yeah, I think it's the lowst numbered audio channel in the stream that is used. This seems to work for UK DVB-T. As dave says, the rest is WIP.

[Schnurps]

Just to make sure that I understand you right, Chris:

Teletext for VOMP is Work in Progress?
Cool!!! My parents tell me constantly that they are missing this feature...

Schnurps

[Chris]

Now I didn't exactly say that

It is on my wish list, but I havn't really got that far yet.

[Harry]

hi,

i did a little research on the teletext issue and found this:
http://linvdr.org/mailinglists/vdr/2003/04/msg00239.html

according to this info, the teletext gets sent over in a separate
PID. so far, so good.

Transponder 71 (11,83650 GHz, FEC 3/4)
Station    PID Video    PID Audio    PID VTX
Das Erste    101             102               104

the corresponding entry in my channels.conf looks like this:
Das Erste;ARD:11837:hC34:S19.2E:27500:101:102=deu;106=deu:104:0:28106:1:1101:0

everything in order here, i think.

so the VTX PID gets sorted/filtered out somehow by VOMP?
is this true?

thanx 4 lighting things up.

[Harry]

anyone?

[MarkC]

so the VTX PID gets sorted/filtered out somehow by VOMP?
is this true?

VOMP picks out the video and audio packets, and currently it just selects the lowest-numbered PES stream for each. It recognises the "private" packets which contain teletext data but it just ignores them. VOMP currently receives live TV in the same format as a recording, so it doesn't know about TS PIDs.

For some time I've been planning to implement a TS demuxer in the client, which will make selecting audio PIDs easier, and reduce the workload and buffering inside the plugin. I've had it working before, but it assumed a perfect signal. I need to have a good look at how VDR handles missing or corrupted TS packets in order to cause the least disruption to the output.

[Harry]

many thanks for this insight.

OK. this would work for extra audio streams.
i'll just assume that it would work for teletext as well (eventually).

cheers
Harry

[Chris]

The teletext issue has been discussed somewhere on here before. If it is the new MHEG UK style (web page a-like) teletext then forget it, unless someone wants to write an MHEG decoder. I have looked on the net for one, it seems there is only one rumour of it being done and there is nothing available... If it is old style teletext that was discussed in the other thread - then it will be easier no doubt, but it will require someone to write a teletext renderer system for vompclient (and I can't really do this because no UK channels transmit old style teletext in this way).

[davep]

The teletext issue has been discussed somewhere on here before. If it is the new MHEG UK style (web page a-like) teletext then forget it, unless someone wants to write an MHEG decoder. I have looked on the net for one, it seems there is only one rumour of it being done and there is nothing available...

Try RedButton at redbutton.sourceforge.net. I've tinkered with it and it does generally seem to work. However it builds a cache on disk of pages as they are broadcast, and is rather disk-intensive as a result. Maybe one day I'll try tweaking it to use system memory for the cache.

The other problem is that MHEG decoders expect to use a specific font (Tiresias), and with substitute fonts the pages don't render accurately. Tiresias is definitely non-free, however anyone who has bought a DVT-T card in the UK has also bought the Windoze application software with it, which includes that font; arguably the font could also be used with the same card under Linux.

[riban]

I have tried Red Button and was fairly impressed. I was intending to look at porting it to vomp. My kids ask for the Cbeebies games and my wife is interested in some of the channel switching interactive services. But as with everything, it is finding time and prioritising. That nice weather is looking rather nice and it's rather hard to see the screen in bright sun shine...