AOA Forums

AOA Forums (http://www.aoaforums.com/forum/)
-   Graphics and Sound cards; Speakers and other Peripherals (http://www.aoaforums.com/forum/32-graphics-sound-cards-speakers-other-peripherals/)
-   -   DVI / Component Out ? (http://www.aoaforums.com/forum/graphics-sound-cards-speakers-other-peripherals/32950-dvi-component-out.html)

saquib 15th September, 2005 08:18 AM

DVI / Component Out ?
 
We friends are planning to watch movies on this Hitachi projector. The projector supports progressive scan. Now, it has both DVI and Component Inputs apartfrom standard inputs. 7800GTX can provide output both in component and in DVI. Which one should I use to get highest picture quality from my DVDs in my projector?

:confused:

cadaveca 15th September, 2005 08:54 AM

Dvi

GrahamGarside 15th September, 2005 12:19 PM

You will get the best quality image almost certainly from the DVI ports

Aedan 15th September, 2005 04:12 PM

DVI output matched to the native resolution of the projector.

saquib 15th September, 2005 05:01 PM

Thanx for the help.

Daniel ~ 15th September, 2005 05:43 PM

Quality of hook ups bottom to top:
1. composite
2. S-Video
3. RGB (component)
4 DVI or HDMI (same thing, interchangeable with available adapters.

saquib 15th September, 2005 06:54 PM

ok, are there any really significant visual improvement from VGA/RGB (i mean the standard display out that all cards use!) to "DVI" while I play DVDs? For example, to be honest, i can barely find ANY difference while playing movies between composite and s-video outputs. Secondly, are there any VGA to DVI converters? so like even if one doesnt have DVI output, s/he can use that to generate DVI out for some other device?

:confused:

cadaveca 15th September, 2005 08:02 PM

The difference is in how the colour information is handled. svideo will allow for a higher resolution signal as well as the colour info seperated nito 4 channels instead of the one of composite. Component goes so far as to seperate the colours into thier basic cyan, magenta and yellow. DVI is digital, so all the actual signal processing will happen inside the unit itself, and hence less prone to interference and info loss.

Got EpOx 15th September, 2005 08:36 PM

Done and dusted DVI is the obvious choice.

GrahamGarside 15th September, 2005 10:03 PM

The image is rendered digitally any way, then converted to analogue using the cards DAC, then back to digial if it's an LCD projector, that whole process and any degradation of image quality (which is fairly low unless you are talking really high bandwidth settings) can be skipped by keeping the signal digital the whole time.

Aedan 15th September, 2005 11:05 PM

Quote:

Originally Posted by saquib
ok, are there any really significant visual improvement from VGA/RGB (i mean the standard display out that all cards use!) to "DVI" while I play DVDs? For example, to be honest, i can barely find ANY difference while playing movies between composite and s-video outputs.

I'm a little surprised that you can find barely any difference between composite and s-video. For the equipment I have, the difference is quite noticable, with composite giving a somewhat blurry picture (especially in terms of colour), and s-video giving a sharper picture with less blurring of the colour. Of course, if you're not running at the native resolution of the display, then you'll also have to contend with the display device rescaling the image, which can add softness to the picture too.

You can get VGA to DVI converters, but they're expensive, and not generally worth it.

Aedan 15th September, 2005 11:20 PM

Quote:

Originally Posted by cadaveca
The difference is in how the colour information is handled. svideo will allow for a higher resolution signal as well as the colour info seperated nito 4 channels instead of the one of composite. Component goes so far as to seperate the colours into thier basic cyan, magenta and yellow. DVI is digital, so all the actual signal processing will happen inside the unit itself, and hence less prone to interference and info loss.

S-Video seperates the luminance from the chrominance, so there are two channels. Luminance is the information about the black and white picture. Chrominance then carries the colour information, which is overlaid on the Luminance signal.

Component seperates the signal in to YCbCr (which is not the same as YUV and definately is not CMY!). Y is the letter used for luminance, Cb is the blue signal less the luminance signal and Cr is the red signal less the luminance signal. This might not make much sense immediately, as there's no obvious green signal transmitted. However, if you remember that a TV picture is made up of red, green and blue, you can see that subtracting red and blue from the luminance signal gives you the green signal. Hence, component video effectively transmits the green signal three times (and the human eye is most sensitive to green), and the blue and red signals once. However, a component signal still has to be processed, so that the display device can recreate the red, green and blue signals it needs to display the image with!

The DVI signal transmits the red, green and blue signals in a digital form to the display device, reducing the possibility of any analog errors creeping in. However, scaling issues can cause softness with DVI, so it's always best to set the video output to be the same resolution as the display device's native resolution. DVI requires the display device to do the scaling, but not all display devices do very well at scaling!

DVD encoded material is usually limited to a resolution that's not more than 740x480, so your display device would be limited to working with a signal of this resolution. Hence all the work with Blueray and HD-DVD to bring the quality of DVDs up.

cadaveca 15th September, 2005 11:24 PM

Lol. at least i had it mostly right...when i saw you posted the first time i thought that was what you were posting. Count on Aedan to set things right! :p
CMYK is a printing standard...guess where i used to work! Although it is not the same as YCbCr, it's close enough to get the gist of my point. :crazy:

saquib 16th September, 2005 08:51 AM

Ok... thanx a lot guys!!!! I'll be goin with DVI then. :D


All times are GMT +1. The time now is 05:43 AM.


Copyright ©2001 - 2010, AOA Forums


Search Engine Friendly URLs by vBSEO 3.3.0