[mythtv] [mythtv-commits] Ticket #4163: DVB-C in mythtv does not work while it works with mplayer/czap

[Janne Grunau]

On Sunday 02 December 2007 15:34:22 Rudy Zijlstra wrote:
> MythTV wrote:
> > #4163: DVB-C in mythtv does not work while it works with
> > mplayer/czap
> >
> > Comment(by janne):
>
> Janne,
>
> >  Replying to [comment:4 anonymous]:
> >  > IMHO this bug is neither minor nor a candidate for an unknown
> >  > milestone.
> >
> >  It is. Your cable provider is to blame. The transmits a NIT with
> > DVB-S delivery descriptor.
>
> We are talking here about - a likely very small - level 4 in Germany.
> This can be as small as 1 housing complex. A lot of these guys have
> neither the knowledge, nor the money to change their incoming signal
> to conform to DVB-C. What they typically do is to point a dish to
> Astra, receive the TSes, demodulate them, and re-modulate them into
> QAM64 and put them on the cable on some frequency. This they do with
> a de-modulator - re-modulator for each TS they handle. I suspect the
> smaller level 4 to have a fully independent de-modulator / modulator
> setup for each TS.

I know and didn't suggest to ask the provider to fix it.

> For a lot of them, the abbreviation "NIT" will, i suspect, get you a
> blank look. Followed by: But the STB's are taking this well, so why
> should i spent (significant) money on this? And they are typically
> running on a shoe-string for budget......
>
> And yes, the STB manufacturers would love to see them go away, as
> they are a major headache to support in Germany.
>
> The only way i am aware to handle such "networks" is a slow frequency
> scan, and to detect the services in each of the found TS. STB
> manufacturers are not happy with it, as it is slow and difficult to
> get fool-proof (you are not certain to which sat they are pointing,
> so additional info you would want to catch as well (EPG) may be
> difficult to handle).

EPG shouldn't be a problem if they feed the data unmodified into their 
network.

> So you are not alone in being unhappy with them.
>
> I am still hoping for a better solution in Myth.

I don't think there can be done much. The best option I can think of is 
making channels.conf import working and hope that someone distributes 
the channels.conf.
We should of course ignore delivery descriptors the scanning card 
doesn't support and insert the actual tuned parameters into the 
database.

Janne