[mythtv-users] Multiple tuners with different channels

[Dave]

 --- "Joseph A. Caputo" <jcaputo1 at comcast.net> wrote: > > -----Original
Message-----

*snip*

> When you specify a video
> source, it
> uses an external program (tv_grab_<region>) to grab your selected
> provider's
> list of channels.  Yes, a 'channel' (here meaning a television
> network) may
> exist in more than one source, but it will not have the same
> frequency in
> both sources.  So, we *do* need to maintain separate database
> entities for
> each channel, even if they are the same television 'network'.  What
> we would
> really need would be a way for Myth to be able to determine that two
> channels are equivalent in terms of content (a 'networkid', i.e.,
> 'CNN'
> (network name), 'WPVI' (television station callsign) or a numerical
> equivalent).  

Ah, now being a Brit, we don't have the same kind of TV Networks over
here, so that's not something I'd thought of.  Over here, although we
do have national stations, which the local station will opt-out of with
local programming from time to time, in most cases that local variation
will be the only option available to you for that "network", so it
really only appears as a single channel.  That is changing very
slightly for some D-Sat viewers, but on the whole, that's the way it
is, BBC1 on analoge == BBC1 DTT == BBC DCable == BBC1 DSat, etc.

> 
> I'm not saying it's impossible, but when you look at all the
> discussion and
> effort that went into something as conceptually simple as separating
> the
> concept of channum/chanid from the tuner frequency, and consider that
> this
> is (IMHO) a much more complicated idea, you begin to see that it's
> not as
> simple as all that...

Yes, the more I think of it, the more I (generally) see what you're
saying.  I don't see that you could have two tuner cards where channels
have different frequencies on both (unless your slave backend is MILES
away ;), but yes, I can see that if you had an analoge tuner, a DTT
card, a DSat card, an external line-source, etc.

It does sound a lot more complicated that I originally thought,
although I agree, not impossible.  I'd imagine it would involve another
table, listing channel and sourceid, then type of source, some columns
that are going to be common for each type (like tuning frequency, even
if the numbers there have different meaning for different types of
source), some DVB specific columns (all DVB sources will have FEC's,
PIDs, etc), and then some that are specific to some sources and NULL
for other sources, as well as some kind of favourite or quality
ranking.  That table would possibly contain channels several times, and
would be seperate to the table which defines a channel in terms of
callsign, "number" listings source, etc.

All certainly much more than the "minor adjustment" that I was
originally thinking of.

> 
> Anyway, I don't mean to discourage you; I'm sure that if there is
> enough
> interest someone will tackle the concept you've put forth; I just
> wanted to
> give you an idea of the magnitude of what you're suggesting.  Of
> course, I
> could also be completely wrong in my assessment of the complexities
> involved
> :-)
> 
> -JAC


No, that's fine JAC, it has made me realise that there are a massive
number of combinations possible.

I still don't know how best to set up my system though ;)

--Dave



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