[TriLUG] Best HD/TV or Regular TV card for linux

[Jason White]

* Joseph Tate (dragonstrider at gmail.com) [060327 12:51]:
> I just bought a HD5000 air2pc HDTV Capture card
> (http://mythic.tv/product_info.php?products_id=46), and thought I
> would share my experiences with it:
> Unless you have a very recent video card and a very fast CPU, video
> playback sucks, whether live or recorded.

Yes, you need a fast CPU for "playback", but the HD5000 records HD
perfectly fine.  You just need lots and lots of storage.  I have it in
my Myth box (Athlon XP 2500+ / nvidia FX5200), and I record all sorts
of stuff OTA.  Depending on the quality of the HD source
(720p/1080i/etc), I get mixed results when trying to playback on the
same box.   So, the card itself works just fine -- it tunes fast and
does exactly what it's supposed to do.   As well as HD/ATSC, it also
supports QAM (for those cable channels that are not encrypted).

> Before you jump on a HDTV capture card, play the clip at
> http://pchdtv.com/downloads/tst.tar in mplayer or xine on your target
> system.  (Note that it's an mpeg stream, not a tar file as the url
> implies).

Agreed -- it's important to test your target system, but the video
capturing is the easy part, you don't need much power at all to do
that.  Playback is the hard part -- which is why I love Myth's
frontend/backend architecture, where you can have a "backend" server
in the corner of your house capturing all the data, and then any
frontend machine (TV room, laptop, etc) can "playback" the video.

> I thought my Athlon XP 3000+ with 512MB ram and rinky-dink video card
> (ATI 7500 and Nvidia GeForce 2) would be fine, but it chews all my CPU
> and chops like crazy.  I just bought a new GeForce 6200A with HDTV out
> and it seems to be able to play that clip ok, but I haven't had a lot
> of time to really play.  My cpu usage still seems to be very very high
> though.  The nuts and bolts of it is: you need a really good mpeg
> decoder to do decode hdtv signals in realtime.

If you're really CPU-bound, and you have an Nvidia card, try XvMC.
http://www.mythtv.org/wiki/index.php/XvMC

Jason