[mythtv] DVB EPG (Was: [PATCH] Beginning radio pvr support)

[Kenneth Aafløy]

Hi,

>> I haven't really looked into this yet, but is the now/next data synced
>> with the show, ie, if a show starts late, the now/next data will only be
>> updated when the show actually starts or when it is scheduled to start?
>
> In the UK on freeview, you are lucky if the data is there and for the
> correct day...  Actually it's not quite that bad, but sometimes it seems
> to get messed up quite badly.
>
> Rumour has it that from "Jan 2004" we will get full 7 days epg....  Anyone
> still got a normal box plugged in to see if it's broadcasting yet?
>
> I think it handles schedule changes, but I doubt it handles very short
term
> delays or over-running programs (perhaps though...?)

>From my experience the now/next data was very static (DVB-S: Thor 1W).

>> If it is in fact when the show actually starts, then this could make an
>> interesting addition to the scheduler. Ie, an option to 'use DVB
>> now/next data' where Myth would check the now/next data to see when a
>> scheduled recording has actually started and begin the recording at that
>> time. If no card is free at the time, it could fall back to the EPG
>> obtained from XMLTV.
>
> Kenneth has already kindly built a parser into the DVB code.

Which he ripped out before submitting to CVS. Search the mythtv-dev archive
for an older version of the dvb-patch (don't think I modified it after
releasing the .5 version or so). If you can't find it, give me a haul,
and I'll see if it's located somewhere on my disk still.

>> The epg info is continuously broadcast with the tv data as I understand
it.
>> You would simply write extra code to continuously update the epg data in
the
>> database based on the DVB data.
>
> Your problem comes if the user never changes channel (well, changes mux
really).
> VDR has a process which early in the morning flicks across all multiplexes
and
> makes sure that it has all the new data at least once that day.

The event that the user has LiveTV on for 24h is very unlikely, and the
process
seems to work well for vdr users. Also it should be pretty simple to
implement
in MythTV as well, if the now/next data or epg feed of any other kind is
found
to be accurate and maintained.

> Basically have a look at the DVBChannel.cpp code (I think) and see if you
can
> use it to dig out your DVB epg data (also look at the tools from Metzler
bros,
> etc which can dump all the data out of a live stream so you can check if
you
> are doing the right thing in myth code)

DVBSections.cpp that is, and there is heaps of debugging statements in there
to
enable printing of just about anything. Just for checking if it exists it's
probably easier to just use the Metzler code (www.metzlerbros.de).

Also I think there is proprietary solutions to the EPG implementation out
there,
i.e. I destinctly remember that MHP (Media Highway PLatform) has this in the
specs.
But then again I doubt that DVB-T in UK uses this platform.

Kenneth