[mythtv-users] Output to HDTV

Shane Warren swlists at mit.midco.net
Sat Jan 3 17:28:57 EST 2004


Peter Lee wrote:

>This is possibly unrelated, but:  Are you sure this is a (de)interlacing
>problem?  I am also running with a GF4MX (440) on an nForce2 board.  What I
>find is that if I have twinview enabled then I get pretty annoying tearing
>of the image (especially during fast panning).  As far as I can tell (from
>googling around), my video card is not able to do vsync properly when
>twinview is enabled.  This affects any video application (mplayer, xine,
>etc), even if the application's vsync and double-buffering options are
>enabled.
>  
>
I actually have my DLP rear projector hooked up through straight VGA 
right now, as soon as my new card arrives next week I will be using 
DVI.  Right now DVDs look unbelievably excellent (at 1280x720p), no 
tearing as I see on interlaced video from the tuner cards.  At the 
moment I'm not using twinview, the onboard on my nforce2 board only has 
VGA out, so I bought an GF4MX440 w/ svideo, vga, and dvi out, mainly so 
I could get DVI out and also try the twinview out svideo out.   So I'm 
not 100% sure its an interlacing problem, but lets say I'm 99% :-)  What 
I don't get is why some people w/ hdtvs don't seem to have the 
interlacing problem, my current theory is that most people are running 
at 540p which most hdtvs may de-interlace since it may take it as 1080i, 
again this is just a theory, or maybe your TVs are always de-interlacing 
even if its a progressive input (seems unlikely).


My understanding of this is that if you display an interlaced video on a 
non interlaced display you are sure to get interlacing effects unless 
the monitor device deinterlaces it or the output device deinterlaces 
it.  BTW is the interlacing effect is really like a tearing from a non 
vsync display, the best way I describe an interlacing effect is you see 
a bunch of horizontal lines through objects especially when they move 
quickly? 


I'm sorry to hear that twinview has a different way to screw up video, 
hopefully I can make my new card work, if not I'm back to square 1, 
probably then I'll have to use the kerneldient filter if my 2500+ can 
take it.

>Or a separate front-end for each input on my plasma monitor.  ;-O
>  
>
Hopefully it doesn't come to that, then you have to switch inputs all 
the time ugh..

Shane



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