[mythtv-users] Beginner Question

Joseph A. Caputo jcaputo1 at comcast.net
Mon Dec 20 21:49:40 UTC 2004

On Monday 20 December 2004 15:19, Brad Templeton wrote:
> On Mon, Dec 20, 2004 at 10:54:32AM -0500, Joseph A. Caputo wrote:
> > Again, AFAIK, there is no consumer-level HD analog capture
> > solution. You can't capture HD over composite or S-Video, and a
> > component video capture card would cost > $USD 1000.  So,
> > *theoretically*, yes, an HD
> These cards are also meant for the camera capture market, I think.
> As you note, they are capture, not compression.
> For us, it would be far simpler to capture DVI, which is already
> digital, and for which decoder chips are available.   DVI can be
> thought of, at 1080i as 1.5 gigabits (24 bit colour) from 3 500mbit
> streams.  Decoding that is well within the realm of cheap hardware if
> you make enough of them.
> It is, as noted, compression that is the killer.  You can't write 1.5
> gibabits except to a striped array of several drives.
> Though as I noted in another message, I see it as possible that a
> cheap card could downsample the 1080i signal to perhaps 1280 x 540
> (almost all the res of most HDTVs sold today) and then do some basic
> compression and if we can get it down to something more like 100
> megabits, then you have a shot at recording it -- for immediate
> post-compression of course.

But the reality is that none of this is available now.  DVI decoder 
chips may be available, but are there any cards on the market?  Any 
word of anything coming to market soon-ish?  RIght now these things 
(what few there are) are also in the professional price range.  Also, I 
realize that hard drive capacity is becoming cheaper, but keeping a 400 
GB drive dedicated as -- essentially -- a scratch disk is not my idea 
of a killer app.

I think a more likely (or a least 'to-be-hoped-for') progression of 
events is that hardware encoder/chip technology/prices will advance to 
a point where a consumer-priced HD encoder card will be possible.  
Imagine: DVI in, real-time compressed to some kind of MPEG or other 
codec.  That's the gold ring.


More information about the mythtv-users mailing list