[mythtv] DVBCam Class

[Kenneth Aafløy]

On Tuesday 21 September 2004 15:54, Taylor Jacob wrote:
> >  From a limited observation following the lists here: I think the hdtv
> > works by decoding the TS and repacking into a new ts with constant (and
> > new) pid's.  I'm not sure why that is done though...?
>
> Thats where my confusion comes in.  I am not quite sure what wrong with
> that, and if its actually not just a programstream.  I suspect its a TS
> stream since its encoding the PIDs to something other than 0xE0 for video,
> and 0x80 for PCM audio (i can't recall what AC3 is now).  If I can use the
> same code and store something that my PVR350 and the NupplePlayer will play
> back I don't know if it will make any difference.
>
> There also may be some people on the list that can clarify what the true
> difference betwen a PS and a TS is and keep me from reading the MPEG specs.
>  If not i'll figure it out because it didnt look to difficult from a quick
> skim of the MPEG specs.

A transport stream is multiple program streams packed in a single stream.
Read the Mpeg specs if you are hungry for more information.

> One thing I would like to see if someone else is interested in working on
> is making the Frontend be able to handle more than just Audio/Video
> streams..

Already done, revision 1.99 in: 
http://cvs.mythtv.org/cgi-bin/viewcvs.cgi/mythtv/libs/libmythtv/avformatdecoder.cpp

I also had a version of this that also displayed the streams in the osd menu.

> This is needed if you want to tune in an Audio DVB station, but 
> also when you are using a DiSEqC motor.  Since video is expected within 15
> seconds sometimes that is not enough to move my dish and start streaming
> video into it if it has to more more than say 10-20 degrees.

That 15 second assumtion is nothing more than that, stupid. There should be an 
interface for reporting whether the recorder has crapped out or is still 
waiting on something to be able to stream.

> I can extended the tuning timeout in dvbchannel no problem, but based on how
> long it has taken me to get a true understanding of what 
> dvbchannel/recorder/sections is doing I don't think it will be that quick 
> for me to make the frontend / recorder code allow it to take longer and if
> so display some message.

I also made a workaround for this in my exp. patch set, but nobody cared, and 
it had some regressions, so I dropped it. http://kenneth.aafloy.net/mythtv

> It would be great to make it say "Moving dish 
> please wait.." instead of killing the frontend (or timing out).

Yea, would be extreamly cool, and actually user friendly.

> I have figured out how to parse the DVB Radio Channel Titles/ID3 data
> streams (whatever you call it) at least what we can get in North America, 
> so if someone did make it so you could display some text on the screen I
> could add that in so it would be capable of displaying the titles as well. 
> It would require writing that data to the RingBuffer, but thats probbably
> not that hard..

Why would you write this data to the ring buffer? Why not just stuff it in the 
program info class?

Kenneth