[mythtv-users] E: nvidia new drivers hdtv/interlacing, any benefit for us non HDTV people?

Chris Vargas ceenvee at yahoo.com
Mon Jul 5 07:22:41 EDT 2004


--- bjm wrote:

>> The thing that is apparently not happening, is that

>> the drivers (or the video circuitry of the card 
>> itself, or both) are not letting the interlaced
signal 
>> _pass through_ to the interlaced output of the
card. 
>
>See the rest of my previous replay. The recorded scan
lines 
>are not simply displayed on the same scan line during
playback 
>because even at 640x480 the image is being rescaled
to fit in 
>the underscanned display area which is something less
than 480 
>lines. 

OK, so the question then becomes: is it possible _via
software_ to get nVidia tv-out to NOT do this scaling?
Or is this a hardware limitation of nVidia's tv-out? 

I understand the overscan problems that would arise if
this could be done, but I would think that correct
playback of interlaced video would be the first
priority, at least as far as MythTV goes. (I do
realize that for other non-PVR applications, you'd
want your whole desktop to fit.)

>> Therefore, fields are not being maintained, and 
>> therefore the video image is affected. Some people 
>> seem to be able to see this, some don't. 
>
>Placebo effect. 

I agree, with respect to the new drivers (at least
from what I'm hearing). 

I was actually referring to the more basic ability of
someone to detect whether they're getting correct
interlaced source playback via tv-out, regardless of
which nVidia drivers are in use. It's very obvious to
me when it's not correct--I'm surprised it's less
obvious to others.

>> Again, at least with the PVR-x50, the fields are 
>> definitely there and maintained. 
>
>Um, capture of the input signal? 

Yes sorry, capture of the input signal. And it's good
to know that the other capture cards preserve field
info when capturing at 480 lines (capturing at 240, I
imagine, tosses out every other line).

Thanks.


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