[mythtv-users] Capture card with component video in?

[Brad Templeton]

On Wed, Jul 26, 2006 at 08:32:37AM +0100, Justin Hornsby wrote:
> Did you know that a good proportion of video decoders (the bit on
> tuner cards which digitises the video) these days have the capacity to
> take component or RGB inputs?  Of course they probably _can't_
> digitise anything above 720p (some even less I expect) but the
> difference in capture quality would be worth having all the same.  Yet
> all the tuner card manufacturers choose not to provide these kind of
> inputs - go figure.

Why would they not be able to digitize above 720p?   720p and 1080i have
a pretty similar "pixel clock" -- 55M pixels/second for 720p, 62M p/s for 1080i.

The hard problem is not digitizing so much as compressing, since most hard
disks won't let you write data that fast (it's more than 150 megabytes/second)
and even if you could with a striped array, it's not really practical.

Indeed, with DVI inputs, you would not need to digitize at all.  It's all
about the compression.

We're on the cusp now of somebody being able to make a compression card that
can be afforded.  Due to the effort to stamp out DVI it would also have to
digitize.   If you were willing to take some compromises, such as 1280x1080i
(for native 1280x720 tvs) or even 1280x540, or lower frame rates, you could
already be doing it.