[mythtv] DVB integration - first attempt!

Edward Wildgoose Edward.Wildgoose at FRMHedge.com
Thu Apr 24 14:42:17 EDT 2003


> I fixed a bug and uploaded version 3.

Can I get a rough idea as to the diff.  I already applied v2, this would help.

> The dvbstream stuff is in libdvbdev and a bit in dvbrecorder.cpp. dvb* 
> files do the DVB stuff internally, stream* files try to call external 
> programs to do the work. The rest are a few structural and cosmetic 
> changes to make it all work.
> 

I have had another longer look at the code, and I can see most of this now.  I had kind of assumed that the stream interface would be the dvbstream interface!  I have also had a look at the dvbstream code in CVS and it seems reasonable enough - do I assume that you have basically ripped that out directly?

> >I also have a "full" card - is this likely to present problems with getting your code to work?
> >
> With the current code, it might. It assumes that I get a full transport 
> stream from the card, which the full cards are not capable of, at least 
> that's what I read.
> 
> I'll have to build in some support for that.

Hmm, could be an issue.  I think you are right that you can't get the full transport stream out - I will ask the question on the DVB list though.  However, the flip side is that to get a stream out of the full featured cards is about 3 lines of code!  (according to the readme in the DVB driver directory)

> 
> >Finally, what are you expecting to see in the updated channels table (SQL).  For example to tune to BBC One in crystal palace area is freq 505833, vpid 200, apid 201 qam=16 (or something similar) - what should I enter in the table?
> >
> The same format as dvbstream expects. Unfortunately, I don't know 
> exactly what it is.

Hmm, where is this defined?  The code seems to get it from the command line and has some hardcoded defaults for important stuff like QAM, etc

> 
> Set e.g. "freq=xxx|pol=V|symbol_rate=22000" in the tuning column and 
> "pid_vid=768|pid_aud=769" in the subtuning column of channel. (These are 
> new, see cvs.sql.)
> 
> >Most of it seems to compile OK, but I need to change a few settings to finish the compile.
> >
> What did you have to do?

Nothing major.  My qt headers seem to be in a different location.  Also, I didn't have the DVB headers installed because I was testing the latest CVS install (and so the headers are somewhere different at the moment)

> >Would having shell access help...?
> >
> Yes, definitely. I could try out the code and fix some of the problems. 
> I probably can't see much of the resulting video stream, but it could 
> help sort out the problems that occur before it.
> 
> If you're at home at the moment, I'm on IRCNet <http://www.ircnet.org>, 
> channel #mythtv.

Contact me offlist and I will see what I can do.  I think it would be best if we rigged up a test harness first though so we can establish that the DVB stuff works.  I will buy a Nova-T card if this is the easiest way to get going.  Where are you based anyway?

Basically we need a simple program which just does channel init, then record, and spits the output to either stdout or a file (can then pipe into mplayer to check it is real).  What do you think?



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