Newsgroups: sci.electronics.misc
Subject: Re: Convert DVI-I analog signals to Component Video?
References:     
Leland Hosford  writes:

> Tomi Holger Engdahl wrote:
> 
> > Leland Hosford  writes:
> >
> > > Tomi Holger Engdahl wrote:
> > >
> > > > Leland Hosford  writes:
> > > >
> > > > > ...
> > > > >
> > > > > 1) What are the differences between Component Video (red, green, blue)
> > > > > and the analog video signals in a DVI-I connector (analog red, analog
> > > > > green, analog blue, analog horiz sync, analog ground)? Or, where I would
> > > > > find specifications for those two signal types.
> > > > ...
> >
> 
> In looking into this more, I notice that the Component Video inputs to my TV are
> actually labeled Y, Pb & Pr but they are color coded red, green & blue. In view of
> that, I think that the color coding my have confused me but I'm not exactly sure.
> Does anyone know for certain whether or not RGB and component video are two separate
> specifications?

There are RGB, Y, Pb & Pr and some other component video signals.
By tecnical terms RGB is a component video format, but usually
when somebody is refererring to RGB they use term RGB.
Ana same people when refer to "component video" they usually
refer to Y, Pb & Pr.

RGB and YPbPr are two different video formats. 
THe difference between them is how the signal
is coded to those wires. If you connect Y, Pb & Pr
to RGB or other way you do not et peoper picture out.

Some peorfessionl video companies make converter for this
and you can find circuit diagram for this kind of conversion
at http://www.epanorama.net/videocircuits.html#converters

You are not the first one who have confused with the
RGB - YPbPr issues. The color coding you are refereing
on some equioments is really confusing many people.
You can claim the equipment manufacturers for that...

> >
> > > > > 3) Does anyone currently market such a converter?
> > > >
> > > > There are external VGA to TV converters on the market.
> > > > Some have RGB output suitable for TV also. Quality
> > > > and prices vary greatly. I have no special recommendation
> > > > for a device to buy.
> > > >
> > >
> > > I would much rather find a good commercial product that outputs RGB than build
> > > something myself. I had, unfortunately, only found one that converts the video
> > > to S-video and it doesn't give a very good image at all (despite its
> > > advertising claims).
> >
> > VGA to TV industry is advertising claims are usually crystal
> > clear picture in nearly every product. But the reality is
> > much worse both because of limitations of different video
> > formats itself and both poor implementations of the conversion
> > used in most of the product.
> >
> 
> The converter I purchased converts VGA to S-video and claims a crystal clear
> "1600x1200 every time". The reality is that the 640x480 output by it is worse than
> the 640x480 S-video output by my ATI all-in-wonder card (it is not as sharp and the
> colors are off). Higher resolutions are not even useable. I'm seriously considering
> sending it back for a refund.
> 
> I have found one VGA to component video converter ( see
> http://www.smarthome.com/77706.html ) but it clearly says "This converter is not
> intended to connect a PC to a Standard Definition television" which is what I am
> trying to do.
> 
> --
> 
> Leland Hosford
> 
> To send me e-mail remove "NOT!" both times it occurs. Sorry for the inconvenience;
> I'm trying to avoid giving the spammers my address.
> 
> 

-- 
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
http://www.epanorama.net/