Video Primer!
Why Bother With RGB??
Well, quite simply,there is no better picture. Period. Better than S-Video, better than video, and light years better than the picture you get from your RF switch. Here's why:

Internally all modern computers deal with graphics as individual pixels while generating a display. Each pixel is defined as having a certain colour value, defined by it's RED, GREEN and BLUEcomponents. These are each assigned a numerical value, which you've probably dealt with if you've ever used a paint program. This is about pure as it gets. Every time you 'step down' this signal, you lose some quality, not only in the conversion process, but in the subsequent cabling as well. Also, your TV has three 'light guns' inside generating the picture you see, and if you've dropped from RGB to something inferior, and your TV has to seperate this signal into RGB again.

The different methods of graphic transmission, from the best to the worst, are as follows:

RGB - as mentioned, is the best. One wire for each colour, usually with it's own RF sheilding to reduce any interference and any subsequent quality degredation. Nothing is better. The original image is preserved as completely as possible, all the way from the source to the display. The display device doesn't have to do any work seperating any of the combined or composite signals into the red, green and blue channels for final display.

Colour Difference or Component Video. Component Video is a bit of a misnomer - RGB is technically also component video, or video whose components are transmitted seperately. Usually, when someone refers to Component Video however they're referring to Colour-Difference video. Dan's Data explains this as follows:

The first channel is luminance, (notated Y, the standard abbreviation for intensity). The luminance is the signal’s brightness information only, and includes no colour data. The Y signal by itself gives a black and white picture. The other two channels are called colour difference. They’re notated R-Y and B-Y, and are the difference between red and the luminance and the difference between blue and the luminance, respectively. The colour difference channels can be algebraically recombined with the luminance to give a full colour picture, without having to transmit the green data that, on most video, takes up more bandwidth than the other two colours put together (on average, green is 59% of a video signal).

Now that's not really all there is to it. DVD discs store their video data as component video, but it's compressed, where the Luminance (Y) channel is mostly left alone, but the R-Y and B-Y signals are compressed using a technique similar to MPG1 video. Not all compenent video sources are compressed - the Playstation 2 for example, allows the use of uncompressed component video for the display of games and computer data - but it's DVD output is, of course, compressed.

S-Video - The RGB components are combined into two wires, Luma and Chroma (Y + C), or Brightness and Colour. Again including their own shielding to prevent interference.

Video - The yellow wire on that weird yellow-red-white cable you got with your Super NES but never used. This uses one wire (With it's own shielding) to carry all this video information. This is generally a pretty good picture, but depends greatly on the quality of the wire, and the quality of the generating & receiving equipment. Also known as NTSC video, or the V from A/V. Usually accompanied by a red and/or white AUDIO cable.

RF - This goes into the cable plug on the back of your TV. This is one wire, shielded, carrying not only the NTSC video information, but also the sound information as well. In the case of the cable coming out of your wall, this one wire contains many (In some cases hundreds) channels. Sound, Video, closed-captioning, alternate audio channels, radio stations, and a lot of radio interference (noise).You may ask:

So what?

Well, here's what: Every time you add a signal to the line, you assign it a different operating level, or frequency, to keep it different from the other signals. Imagine a large pipe going into your TV, and you've got each signal assigned a different level. The topmost level might contain the video, the lower containing sound. For cable, imagine hundreds of 'streams' flowing in, through this narrow pipe.

In a perfect world these streams would stay where they were supposed to and the picture would be great. Ever been to a friends house where his channel six looked better or worse than yours? Our world isn't perfect. We're surrounded by all manner of electrical noise, radio stations, CBs, police, your TV, the toaster, the blender... Each of these generates an electrical field which can (And does!) interfere with your beloved game system's video output. Each of these pushes the signals around a little and you get what's called CROSSOVER.

Crossover is bad.

Crossover blends the edges of one signal into another. Your TV doesn't quite handle this as well as you'd like, so you get a poorer picture. With hundreds of channels, each with their own information 'streams' pouring into your house, and all around your RF cable from your game machine, you can imagine how much of this crossover is occuring.LOTS.

Which is why we seperate the signals. The more you can keep the signals apart, the better they are going to be preserved on their way to the display, in this case your TV.

RGB is godlike because it keeps every signal seperate.

Get it?

Good!

Questions? Email us!




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