[NCLUG] MythTV Questions

[Brian Wood]

DJ Eshelman wrote:
> You know, I guess this thread is a good as any to ask this question, but 
> does anyone have any ideas about best price/performance video capture 
> cards?  Especially ones with component and Svideo INPUTS (lots have 
> outs, but I don't know what to do for ins).

Actually few capture cards have video out of any sort. The PVR-350 does, 
but I'm not aware of others.

Component inputs are also rare, though the promised Hauppauge device, 
due out next month, will have them.

Most capture devices have composite and S-Video inputs.

> Basically I've got a lot of VHS tapes that I'd really like to convert to 
> MPEG4 or H.264 files; has anyone had success/failures?  There's 
> obviously this list:  
> http://www.mythtv.org/wiki/index.php/Category:Video_capture_cards  but 
> I'm curious about local experience...  Obviously there's the option of 
> the Hauppauge PVR-150 at about $60 for SD captures and the PVR-150MCE-LP 
> is nice for low profile.  I was intrigued by the Plextor ConvertX (which 
> has hardware encoders, but I wonder how flexible/compatible that would be)

Well I happen to own all of those.

The PVRs are pretty much the gold standard for SD capture. You can find 
cheaper cards but you KNOW the PVRs will work well with myth, including 
things like CC. The remote works well, and the setup for it is included 
in all of the "all-in-one" Myth distributions. Basically it's "Gonna Work".

The Plextor is a great device, and is available for $50 these days 
(after rebate). It does have some limitations:

Although the Plextor will do hardware compression for MPEG2 and MPEG4 
(including the DiVX-branded variants), only the MPEG4 modes are 
supported by MythTV, so if you need MPEG2, say for burning DVDs or 
streaming to a device that can only play MPEG2 (like a MediaMVP) you 
will have to transcode first.

Because it uses a chip that was originally designed for security systems 
the Plextor does not encode the audio into the MPEG stream (as a PVR 
does). It appears to your Myth (or any other Linux) system as a sound 
card input, though ALSA handles it well. You have to use your main CPU 
to compress the audio (assuming you want to, you could use uncompressed 
audio if you want to waste the space), but MPEG3 audio compression is 
not really CPU intensive.

I would not use the Plextor for recording progressive scan stuff. It 
de-interlaces everything before compression, as was mentioned the other 
day on this list I believe.

Since it is a USB device, if you have a lot of buss contention there 
could be problems, but unless you're running hard drives or something 
like that I wouldn't worry about that too much.

It does require a "wall wart" power supply, if that's a concern to you.

And of course remember that the Plextor is an analog SD only unit.

Still, if I didn't already have 2 of them I'd grab one for that $50 price.

One other thing: The Plextor (and the Hauppauge for that matter, except 
the OEM versions) come with software that includes access to scheduling 
information. Whether using that for MythTV is a violation of the EULA is 
a matter of conjecture, but it's something to be aware of.

Having that Windows or Mac PVR software might make it easier to sell the 
unit should you ever decide to, or perhaps if you pass it along to 
somebody who doesn't want to run Linux.

Finally, for OSS purists, the Plextor requires non-GPLed modules, the 
PVR modules are now part of the kernel. This doesn't bother me but it 
seems to distress some folks.


> Oh, and I just noticed that the price on the AMD LE-1600 45W processor 
> is down to around $40- does anyone know if that would work well as 
> opposed to a VIA C7 for a fanless/singlefan box configuration?  As Paul 
> was saying- the big huge loud box usually isn't a big hit :)  Maybe 
> building a box with that would be cheap and quiet...

The usual question: Do you want to do HD? Should be no problem with SD 
stuff but it might get pushed a bit for HD, especially if you are not 
getting XvMC help from your graphics card, which is likely in a small 
format system.

Looks like great progress is being made in using the AppleTV device as 
an HD-capable MythTV frontend, both under Mac OS/X and pure Linux. I 
don't think you could buy a full machine using the LE-1600 for less than 
the cost of an AppleTV, especially as they are available refurbed. A 
nice quiet small solution.

beww