[mythtv-users] Re: Considering a MythTV

[Jarod C. Wilson]

On Monday, Jason Williams wrote:

> Thanks for the response Jarod, you have given a lot of good 
> information.

No problem. :)

> I am liking what I'm reading but do still have a few concerns.

Understandable.

>> Use mondorescue to generate a bootable full system restore CD. Boot 
>> off the
>
> CD, reinstall the system exactly as it was in no time whatsoever...
>
> That's a new one for me.  I've made note of mondorescue for my tech 
> kit.

http://www.mondorescue.org/

VERY cool software.

>> Ah, well, in that case... The PVR-250 at its highest settings uses
>> quite a bit more disk space, because it does hardware mpeg2
>> compression, instead of software mpeg4. mpeg4 uses about 1/4 the disk
>> space, if I recall correctly, but there is also an option in the 
>> latest
>> rev of MythTV to transcode recordings from mpeg2 to mpeg4 after they
>> are done (I haven't used it myself; I have plenty of disk storage to
>> just use mpeg2).
>
> How much more?  Could you give an example of a 30 min program?  1 
> Hour?  2
> Hour?

Running at the full resolution for NTSC (720x480) and the maximum 
bitrate for the PVR-x50, hour-long shows usually take about 3.8GB on my 
system. That is more or less linear, so you can extrapolate from there. 
I haven't actually done any mpeg4 captures, but the MythTV docs say 
typical values for mpeg4-encoded shows range from about 700 MB, upwards 
of 2GB per hour, depending on your settings.

> I didn't notice the transcoding options.  Are they automated through 
> the
> GUI?

Yes, you set this up in the GUI.

> Can they also be done at a later time as opposed to immediately after
> the program?

Not sure...

> So essentially this would allow you to watch the program in
> MPEG2, but archive it in MPEG4?

Exactly. Well, sort of. Live TV would be an mpeg2 stream, as would any 
program you started watching before it was done recording. Any 
scheduled recordings you were watching after it had already finished 
recording would be mpeg4, I believe.

>> mythmkmovie
>
> Sounds perfect and time saving.  I got the idea of moving the data 
> around
> and editing from my sons system.  The ShowShifter demo doesn't have a 
> means
> of cleaning up the video.

I've heard decent things about ShowShifter, but I betcha you'll be much 
happier w/MythTV in the long run. :)

>> There are ways to control it. I've got Comcast digital cable in
>> Seattle, WA, though almost everything I actually watch comes through
>> without the box, so I just go straight from the wall into my MythTV
>> box. I'll have to muck with the box connection one of these days... (I
>> have a Motorola DCT2224).
>
> I have a lot of channels that I pay for above 150 so I will need to 
> figure
> this out before I even get started.  Most of my premium channels are 
> high
> numbered channels.

Look for info on the IRBlaster.

> I could go straight to the wall in my sons room though.

Or not go to the wall at all. (More to come later in the message...)

>> If you plan on doing software encoding, that PIII-1GHz is NOT
>> overpowered.
>
> Hehe, it's definitely not overpowered but it's paid for already. =)

Paid for is always good.

> I had read these.  Thanks for reminding me.  Seems the P3-1000 would 
> be fine
> for only a single process.

Yep. :( Unless you go w/PVR-x50s.

>> I'm not at all impressed with my AverTV Studio card at all (the remote
>> is mediocre too). I like my PVR-250 WAY better... If you want to
>> minimize costs, use the PIII-1GHz, get a PVR-250 and a large hard
>> drive. A PIII-1GHz is plenty w/the PVR-250. Transcode recordings to
>> mpeg4 when they're done, and space shouldn't be an issue (though
>> continuing to watch TV while a transcode is in process would probably
>> not work).
>> Oh, the AverTV Studio also has some assorted audio issues...
>
> I just might do this to start with.  It really sounds like I should buy
> something around 2Ghz though.  I'll let the budget decide this step I 
> think.

Probably prudent. My main system has an Athlon XP 1700 and the PVR-250; 
I'm going to add the AVerTV Studio to it shortly (it is in my 
test/build box right now). I'll have to do some testing to see how it 
handles...

>> Even with a PVR-250 and a non-hardware-encoding tuner, I think your
>> PIII-1GHz would be insufficient for watching and recording
>> simultaneously. You might be able to do it with dual PVR-250s (or one
>> PVR-250 and one Freestyle, since you don't need 2 remotes).
>
> I don't see the Freestyle on Hauppauge's website.  What exactly is it?

Basically, the PVR-250, minus the remote, from what I understand. A 
number of online vendors carry it...

>> pre-GF4-series cards don't support the
>> nvidia driver's overscan option. I'm extremely happy with the results
>> I've had with my GeForce 4 MX 440's S-Video out.
>
> Overscan?  What is this feature?  Depending on what it is I may just 
> buy a
> new video card.  GF4MX's are not that expensive.

With some televisions, the computer output comes through and doesn't 
fill the entire screen, so you end up with black bars at one or more 
edges of your screen. Overscan blows the image up a bit to fill out the 
TV. I had to overscan a bit to fill out my TV (GeForce 4 MX S-Video -> 
47" HDTV).

>> It doesn't matter a huge amount though, because you can specify 
>> whatever
>> storage locations you want for both live TV buffers and recordings
>> (independent of one another).
>
> Good to know.  Though either way is fine, is this something you do in 
> the
> GUI or the config file?

GUI.

>> Be prepared to spend some time getting everything to work. Some
>> distributions are easier to set MythTV up on than others, because some
>> have pre-compiled packages for almost everything, while others must be
>> installed predominantly from source. Red Hat Linux 9, as I mentioned,
>> is one distribution that has software packages for almost everything
>> you need, courtesy of Axel Thimm's ATrpms:
>> http://atrpms.physik.fu-berlin.de/dist/rh9/
>
> I'm used to this.  As much as I love the concepts and freedoms of 
> Linux, you
> often have to "tinker" with things to get them working right.  Once 
> done
> though, I always enjoy what I've created.

I've got the bare-metal-to-fully-working-system process down under 3 
hours now. My first build, oh so long ago, took about 30 hours... :)

Several things have improved since my first install though, so don't be 
scared off by that number. ;p

> Can you shed some light on the frontend/backend concept of multiple 
> systems?
> My son has a pc in his room that he watchs DVD's on and I recently 
> installed
> the ShowShifter demo on it also.  He's enjoying it, so I'm going to 
> need to
> put something on it to do these functions.  His machine is lower end 
> though,
> and I don't plan to upgrade it at this time.  He has a P3-600 with 192 
> ram
> and does not access the premium channels due to his not having a cable 
> box.

As I inferred above, it would be possible to set up his machine without 
even having a tuner card in it. You could put both tuners in your main 
system, and then run a frontend on his system, which would watch TV 
streamed off the main system. The backend does all TV capture, the 
frontend does all playback, and the two don't have to be on the same 
machine. It is also possible to set up multiple backends to work in 
unison (one has to be the master backend), so you could have a single 
tuner in each machine (or two in one, one in the other, etc). Of 
course, this does mean possible contention between the two of you for 
the tuners. :) The PIII-600 probably wouldn't be good for much though, 
unless it had a PVR-x50 of its own, or streamed video from the other 
system, though you might also be able to scale the rez way down for 
mpeg4... The MythTV docs cover multiple backend issues pretty well, and 
setting up remote frontends is a snap.

My setup shortly will be a PVR-250 and AVerTV Studio in my dedicated 
MythTV box, which is connected to my HDTV, then a remote frontend on my 
Linux workstation, which can watch all the recordings and live TV 
streamed from the dedicated box. I've got a 3rd card that I may try to 
set up in another machine as a non-master backend too, but that's for a 
rainy day (Seattle is actually VERY nice in the summer :).

> Thanks again for the info Jarod, your answers have been extremely 
> helpful.
> I think I'll start ordering parts soon.

Cool. Good luck! We'll all be here if you need help...

--Jarod

-- 
Jarod C. Wilson, RHCE

Got a question? Read this first...
http://catb.org/~esr/faqs/smart-questions.html

MythTV, Red Hat Linux 9 & ATrpms documentation:
http://pvrhw.goldfish.org/tiki-page.php?pageName=rh9pvr250