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[Rebis]

why does a vga kabel make you laugh?

[redwolf]

^^^ Dee Dee Dee

[Rebis]

hmm okay i thought this was a serious forum...time to move on.

ciao

[bullet ballet]

Contrary to what someone posted earlier, componenet and VGA are essentially the same thing.  The only difference is that compnent has the red, green, and blue signals wrapped up along lumina and two chroma channels mathematically.  Therefore, you'd need some sort of conversion device to mathematically extract the original RGB signals from each of the component channels, but the end result should look exactly the same.

[hignaki]

QUOTE(bullet ballet @ Sep 9 2006, 02:12 PM)

Contrary to what someone posted earlier, componenet and VGA are essentially the same thing.  The only difference is that compnent has the red, green, and blue signals wrapped up along lumina and two chroma channels mathematically.  Therefore, you'd need some sort of conversion device to mathematically extract the original RGB signals from each of the component channels, but the end result should look exactly the same.

...no.

[bullet ballet]

QUOTE(hignaki @ Sep 9 2006, 02:27 PM)

...no.

Yes.

http://www.keohi.com/keohihdtv/learnabout/...b_vs_yprpb.html

[sicknasty413]

QUOTE(bullet ballet @ Sep 10 2006, 12:40 AM)

Yes.

http://www.keohi.com...b_vs_yprpb.html

Im no audio/video expert (far from it), but that site compares component to RGB. And, as far as I know, RGB is not the same as VGA (I mean, for one, they have different names.. duhhh).

Component-

QUOTE

A dramatic improvement over S-Video and Composite this breaks down the signal even further for greater quality. This is a set of 3 cables with Red Green and Blue dongles that look similar to the composite connector. Despite the colors being Red Green and Blue in the NTSC standard they aren't actually broken down color wise like that. This cable supports SDTV, EDTV, and HDTV.

VGA-

QUOTE

I'm sure you're familiar with VGA, VGA is very similar to RGB except not only are the colors broken down separately but the vertical and horizontal syncs are broken down as well. This is only ever found an single cable with a 15 pin connector (usually Blue). This Cable supports various computer resolutions

[bullet ballet]

From Wikipedia:

"The term VGA is often used to refer to a resolution of 640×480, regardless of the hardware that produces the picture. It may also refer to the 15-pin D-subminiature VGA connector which is still widely used to carry analog video signals of all resolutions."

In terms of the signal carried over the HD-15 connector:

"'VGA connectors' and their associated cabling are almost always used solely to carry analog component RGBHV (red - green - blue - horizontal sync - vertical sync) video signals along with DDC2 digital clock and data."

While there are different standards of synchronization for the RGB signal, none of the signals are actually different; they are still basic red, green, and blue signals which inform the picture elements which colors to reproduce (all colors of which can be recreated via mixtures of red, green, and blue.)

"An alternative type of componentization does not use R,G,B components but rather a colorless component, termed luminance combined with one or more color-carrying components, termed chrominance, that give only color information. Multiple chrominance channels allow for more precision and speed in mapping the RGB colour space. This componentization scheme is a transformation (in some cases linear, in others not) of the sRGB color space."

Also, if you read this http://en.wikipedia.org/wiki/YCbCr you will see that for our case of the 360, which uses YPbPr, the analogue equivalent of YCbCr, that that particular component standard is a linear transformation of the RGB color space via two defined constants, Kb and Kr.  Sans some of the "idiosyncracies" of the RGB encoding (due to scaling and rounding), the two formats are essentially the same and the original RGB signal can be extracted from a component signal via a true converter (such as this: http://www.smarthome.com/777062a.html) which will perform the necessary inverse math on the component signal.

[hignaki]

But that still doesn't put them at anywhere near the same quality.  One is converted twice (Component, Video Processor/GPU base signal -> Component Signal -> Up/Downscaled component signal), while the other one isn't converted at all (VGA, GPU -> VGA *no change*).

Every time you convert, you lose a bit of quality, no matter how good the converting algorithm is.  VGA not only gives a higher-quality 720p/1080i signal, it also gives you a plethora of other resolution options.

[bullet ballet]

QUOTE(hignaki @ Sep 10 2006, 11:34 AM)

But that still doesn't put them at anywhere near the same quality.  One is converted twice (Component, Video Processor/GPU base signal -> Component Signal -> Up/Downscaled component signal), while the other one isn't converted at all (VGA, GPU -> VGA *no change*).

Every time you convert, you lose a bit of quality, no matter how good the converting algorithm is.  VGA not only gives a higher-quality 720p/1080i signal, it also gives you a plethora of other resolution options.

Yes yes, very true.  But for all intents and purposes, the video looks pretty much the same.  Unless you have very poor component cables or a unit outputting a poorly converted signal, the superiority of the RGB signal generally is almost unnoticable.  At least, with my eyes I've rarely been able to see a difference.

Anyway, with all that said, however, I have read that with 360 people have noticed duller and less saturated colors over VGA a certain "dulled vibrance" that they find preferable over the brighter image of component.  However, I've not used the 360 VGA cable so I cannot comment on the accuracy of those statements.  I do know that on my 1080p display the 1080i image is crystal clear and very sharp; I'd be very impressed if, with so little room for improvement my eyes can manage, the VGA cable yielded any additional clarity.  I think, overall, the VGA cable was only intended for added versatility, to be used by those with displays at non-HD spec resolutions and such.

Another note: I've also heard that those with displays with native resolutions of 1366x768 noticed poor results with the VGA cable since it didn't offer that res but instead 1360x768.  They declared bluriness and a lack of clarity, though it was possible that it was due to poor scaling on the parts of their displays.  YMMV is the common acronym I'd see fit to end with.