Joe Votour wrote:
Newer SVN versions of MythTV apparently do support
pulling in data from the DVB program descriptors (I
live in North America, where DVB isn't available, so I
can't comment on how well it works). I have done some
DVB-related work for my employer though, so I do know
how the system works.
The EIT is the "Event Information Table" (if I
remember my TLAs correctly). The DVB specification
supports sending lots (and I mean lots) of information
within it (the basics such as show start/end times,
program name and genre, but also things like complete
cast lists, MPEG format information, etc.).
The way it works is that within the MPEG-2 stream that
is received by your DVB card, there are video, audio
and PCR (timing) PIDs for one or many "channels",
there are extra PIDs that are added in by your
provider (or may come from the original satellite feed
- regardless of how they got there, they are there).
A DVB card can listen on these PIDs and capture/parse
the data, and turn it into program guide entries.
Most of it is TLV-type (type, length, value) data with
a fair amount of ASCII text.
As I said, I don't know the specifics of the EIT
processing within MythTV, but I would suggest that you
stick with the tv_grab programs if you get accurate
data from them. The reasons that I suggest this are:
1. With the DVB streams that I have seen, the program
guide information within the DVB stream is only good
for 1-2 hours (typically, you get the "now" and
"next", the currently showing program, and the next
program). This means that it will be difficult to
plan far ahead in the future for scheduling, since the
data just won't be there.
2. In order to get complete EIT data, your DVB card
will likely need to hit multiple frequencies to
capture the EIT data on those frequencies. If you
have a single card and aren't recording, this won't be
an issue, but if you're recording back to back shows
and only have a single card, you've got nothing to
tune to other frequencies to find the EIT data. In
that case, you're missing program guide listings.
There is EIT next/now (which you have been describing above) and EIT
schedule.
EIT schedule can cover as many days ahead as the operator wants to / has
data available / has bandwidth available.
Typically, the dutch xml grabber can get 3 day ahead (limit of the
website where it is taken from), and Astra satellites typically have
between 3 and 5 days available in the stream.
Again, this information doesn't come from the MythTV
implementation (I've implemented this in the past, and
it's quite painful), but comes from my knowledge in
the area. YMMV, depending on what kind of hardware
you have, and how much program data you want (I'm
quite happy with DataDirect, and having about 10 days
worth of listings).
Which is only available to those living in the US (which many of us are
not).
Myth takes the program info from the tuned stream, irrespective whether
you are watching that stream or not.
-- Joe
--- Jakob Fix <[EMAIL PROTECTED]> wrote:
Hello,
I've heard that Myth should be capable by now to
retrieve EPG data
from the DVB stream. There seems to be quite some
talk on the dev
list.
Is this correct? If so, which version of Myth
should one have in
order for this to work?
So far I'm using tv_grab_dvb which works fine
although it has some
problems with timezones, and it only gets the
current channel's
transport stream's EPG data.
Oh, and what does EIT mean, and what's the
Event Information Table
difference with EPG
Electronic Program Guide
(wikipedia was no help here)?
The EIT can be used to fill the database needed for the EPG.
_______________________________________________
mythtv-users mailing list
[email protected]
http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
