[EMAIL PROTECTED] wrote:
>> On Jan 29, 2008 3:43 AM,  <[EMAIL PROTECTED]> wrote:
>>> Does that mean a possible route would be to buy a non-scart MVP and use
>>> S-Video.   Or are there other compatability issues, PAL/NTSC etc?
>> Isn't there an svideo out off some scart cables?
>>
>> Martin
>>
> 
> According to Wikipedia "S-Video and RGB are mutually exclusive through
> SCART, due to the S-Video implementation using the pins allocated for RGB"
> 
> So in this case I guess not.
> 
> Also - it seems S-Video is only marginally superior to Composite Video ie
> both are inferior to RGB.
> 
> I think I will start of with the pin 16 mod and see what Composite looks
> like first - it might not be too bad hopefully.
> 
> Thanks for all your help.
> Dave

Hi guys...

I believe SCART contains the Red, Green, and Blue signals separately. 
S-video contains a color and brightness signal.

First I looked at the wiki and, from the pin out, I believe you would 
need a fair amount of electronics to convert an RGB SCART signal to 
S-video.  It's not impossible, but it would be more than just a cable of 
wires. I did notice some support for a Chrominace signal on pin15 and 
pin13.  But they both look like inputs.  If one is an output, maybe 
pin15, then you might be able to develop an S-Video type output from a 
SCART with only wires.  However, I don't know if this variation of the 
SCART is supported by the MediaMVP. Apparently, you make this selection 
by adjusting the voltage sent to the source of the video signal on 
pin16.  Again, I don't know if the MediaMVP supports this.  And, if 
there is a software component, there is also the question if the mvpmc 
software supports this.

Second, S-video is loads better than composite.  Way better.  I think 
this is the reason.  When color TVs where first made, they had to be 
compatible with the old black and white transmissions.  This is done by 
adding the color information on it's own carrier next to the old black 
and white signal.  However, the color signal intercepts or overlaps the 
old black and white brightness signal.  If it didn't they would have to 
spread all the stations apart in frequency to make room.  This would 
most certainly trash all the old black and white TVs.  So, to 
compensate, people put a notch filter in and just tossed the finer 
brightness details and sacrificed a bit of color.  Then they started to 
use comb filters and things got better.  Today, we go to the lengths of 
digitizing individual lines and added them to each other to cancel the 
color carrier which is flipped 180 degrees in alternating lines. 
Further, the upper end sets digitize the whole picture and use computers 
to analyze motion.  Depending on what is found, different sets implement 
different algorithms at different times.

But all this can be avoided if you never mix the color and brightness 
signal!  Hence S-Video (or if you don't like Sony, call it C-Y-Video - I 
think).

Using RGB or it's variations will allow you to skip encoding colors in a 
phase shifting signal.  There should be some improvement, but I find it 
hard to tell the difference between RGB and S-Video.

--------------

As for SCART and S-Video.  I believe SCART will subscribe to the PAL 
50Hz standard.  and S-Video will subscribe to the NTSC 60Hz standard. 
So buying an NTSC MediaMVP may not be the answer you really are looking 
for.  That said, I am thinking the frequency difference is really a 
function of software.  I even think there is a mvpmc configuration that 
lets you switch between the two.  But I caution you that it may not do 
what you want (i.e. make an S-Video signal that is PAL compliant).

---------------

I looked through this thread and I don't see the "nightmare". It must 
have been discussed off-line.  I would assume there is a compatibility 
problem with SCART (i.e. bad definition that let some manufacturers 
create or detect signals which, apparently, look green when the image 
should be black).  Could it be as simple as attenuating the green 
signal?  However, at this point, I question the sanity of such a fix as 
it surly would jeopardize the true colors for every thing else (i.e. 
give everything a slight magenta tint).

Sometimes the synchronization signals are part of the green output.  I 
see where SCART also has independent synchronization signal on pin17. 
So this may be worthless to look into.  But are there any settings that 
enable / disable synchronizing using the green signal on either the 
MediaMVP or on the monitor?  I am guessing here, but synchronizing 
signals would have to go more negative then the black level of the green 
signal.  If generated but not expected, the receiver may clamp the 
negative most travel of the signal and assume that is black leaving what 
the transmitter intended to be black as a visible dark green.  Going on, 
in such a case, attenuation may not be enough.  You would have to float 
the green signal through a capacitor, subtract a small amount of voltage 
with some resistors and cut off the now negative going synchronization 
signals with a diode - or something like that.

I should stop now as this is getting highly speculative.

...good luck

------------------

Hey, look at this:

(http://en.wikipedia.org/wiki/Component_video)
...
(SoG) is the least common, and while some VGA monitors support it, most 
do not. Sony is a big proponent of SoG, and most of their monitors (and 
their PlayStation 2 video game console) use it. Like devices that use 
composite video or S-video, SoG devices require additional circuitry to 
remove the sync signal from the green line. A monitor that is not 
equipped to handle SoG will display an image with an extreme green tint, 
if any image at all, when given a SoG input.
...

So, does anyone know?  Does SCART support an SoG signal?  Is the SCART 
output of the MediaMVP an SoG type signal?  Does Dave have the only 
none-SoG monitor in Europe?







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