KnoppMyth on a 320G drive

[Colin McGregor]

--- Merv Curley <mervc-MwcKTmeKVNQ at public.gmane.org> wrote:
> Hello Colin
> 
> I don't know if you have time to help privately, or
> if it is better to ask my 
> dumb questions on the TLUG list regarding MythTV.
> Maybe just read through 
> this and decide whether or not to write up something
> general for an article, 
> or point me to some insight.  I am in no rush to get
> this working, so don't 
> feel any pressure to reply other than an
> acknowledgement of rcpt.

Well, I am cc'ing this to the list because I am sure
if your having these problems then likely someone else
is having the same problems.

I currently have an article on KnoppMyth awaiting
publication, that just focuses on 
installation/configuration.

> I bought a refurb'd Gateway computer with XP Media
> and a Hauppage PVR 150 
> card. However the Hauppage doesn't have any way to
> connect a remote control.  
> So I removed it and installed the Adaptec Videoh!
> card that I purchased 
> several weeks back. The remote seems to work well
> with the Win software 
> supplied by Adaptec.

Well, there are multiple versions of the Hauppage
PVR-150 card released, some with, some without a
remote. 

> Using the XP Media Center software, displays a
> shockingly poor quality TV 
> picture with the Hauppage card. Using the software
> with the Adaptec  card is 
> about the same, maybe a bit better. The notes with
> the WinDVR software say 
> that it uses software encoding so I assume that it
> doesn't use the hardware 
> encoding available on the Adaptec card. Perhaps the
> the same with the XP 
> Media Centre and the Hauppage PVR150. Perhaps I just
> don't understand when 
> the hardware encoder is used.

The hardware encoder has a CPU on the tuner card that
relieves a lot of the demands off the main CPU. When
doing the above article I didn't want to @#$% my main
MythTV box, so I set-up a 2nd test PC for installs
with an AverMedia TV98 tuner card (as the name
suggests the card is about 8 years old and built
around a Brooktree BT-878 chip, in other words, old
and ugly) which does software encoding. My main MythTV
box and my test box both have a PIII 866 CPU, but big
difference in CPU usage when watching TV. The PVR150
box runs at around 10% CPU when watching TV, the TV98
based box runs around 90% CPU. Now the PVR150 box has
a better video card which will account for some of
that difference, and some difference may be due to
motherboard design and other factors. Still, key part
of that difference is software vs. hardware encoding.

As for picture quality, both boxes look quite good. If
I were betting I would be looking at issues like
quality of cable TV connection, and other cable
related issues. There is one other possible gotcha
area which is noted below.

> When I was down at your installfest, all the Myth TV
> pictures I saw were 
> excellent quality.
> 
> Has this XP quality anything to do with the
> encoding?

Probably not.

> I am using a 19" LCD monitor, set to 1280x 1020, is
> this wrong? Somewhere in 
> the Knoppmyth musings I saw to set ones monitor to
> 800x600. I don't have a TV 
> connected to the video card at this point,  if that
> enters into it..
> 
> maybe Google has the answer, but where can I find
> out in plain english about 
> frontends, backends and all the arcane things that
> are involved in getting 
> Knoppmyth configured?  I have scanned the
> 'settopbox' forums but haven't 
> found much help for a begining beginner. I have the
> MythTV-howto-single* 
> document but I thought much of that was redundant by
> using KnoppMyth. The 
> KnoppMyth install document helps some but the start
> is confusing, talking 
> about using the CD as a frontend with a
> preconfigured backend. How does one 
> go about configuring a 'backend'? Did I miss
> something?

MythTV cuts the job of doing a recorder into two
halves, the backend program that talks to the hardware
(TV tuner, hard disk) and a frontend progrm that works
very closely with the backend. The frontend program
deals with the display and basically talking to the
end user (you). Now, for 90+ percent of people the
backend and frontend programs will run on the same PC,
talking to each other inside the same PC. The neat
thing this set-up allows for is (and were things can
get very strange VERY fast) is you could set-up a
central MythTV server at home or in an office, (I once
worked in an office where every time a budget was
introduced in Parliament the accountants were required
to watch TV at work). With a central MythTV server
(lots of disk space, FAST CPU, multiple tuner cards),
just running the backend program you could have
lightweight frontend boxes scattered elsewhere. The
frontend boxes talk to the backend box over the
network and all is happy...

The preconfigured frontend option in KnoppMyth is only
useful if you already have a box running at least the
backend (as noted most boxes will run both frontend
and backend).

> I did the auto install and can boot it from a Grub
> menu on hdb.  I have gone 
> through the KnoffMyth configuration twice and think
> I accepted all the 
> defaults, right or wrong. But I am sure that some
> need modifications. 

One set of options that can get you trouble is
cable/antenna options. Obviously if you have cable vs.
antenna wrong you will be dead on everything above
channel 13. But in North America there are two cable
set-ups, regular and HDC (the later being a trick some
cable companies use to reduce interference). Get this
wrong and you can I gather expect a 2nd rate image on
all channels. For Rodgers near Yonge & Eglinton the
answer is the default, but your settings MAY vary.

> Like 'Backend Setup'
> 	 I.P. address for the Gateway, this is 127.0.0.1 by
> default,  should it be my 
> gateway router, 192.168.0.1?

These sound reasonable. The right value for the
gateway router will depend on your network hardware
set-up, but 192.168.0.1 is a very popular (but not
universal) choice.

> 	Master Server I.P. Address,  this is 127.0.0.1 by
> default,  it should be ?

Sounds right.

> 	Directory to hold recordings, by default is
> /myth/tv/, but they are to 
> actually go to the mount point for /dev/hda3, I'm
> not sure how to indicate 
> this, in this preconfigured setup.

Yes, these are the normal defaults for MythTV, and
while there are situations where you might want to
change the above, they are not common.

> 	The last part has to do with saving 'transcoded
> [globally] files,  what the 
> heck is this about?

By default MythTV stores files in a format that offers
high quality with LARGE file sizes. There are times
when you want small file sizes and can live with 3rd
rate picture quality. The transcode option is about
converting to a lower quality, small file size.

> Later one is to select a remote controller,  Adaptec
> is first on the list, but 
> once selected, it says it has no drivers.  Do even
> need to worry about this, 
> since it does work?

If it works, leave it alone.

> And on it goes,  this is the part that I think an
> installfest should be 
> focusing on, now that I have lived through this
> first attempt at setting up 
> Myth TV.  I am sure glad that I don't have to deal
> with setting up the 
> database, that is one blessing... Almost every step
> of the the Configuration 
> needs a bit more explanation, what is there doesn't
> help a neophyte a whole 
> lot.
> 
> Thanks for your consideration of these problems.
> 
> Sincerely
> 
> Merv
> 
> -- 
> Merv Curley
> Toronto, Ont. Can
> 
> Kanotix Linux  Ver 2005-4   
> Desktop  KDE 3.5.1    KMail 1.2

Hope this helps.

Colin McGregor
--
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