Umm... what the hell are you talking about?
Component video
Most "RCA" cables include a component video cable, hence the slang (RCA connector really means the type of jack being used). There is a digital component video standard which uses inerpolation, in fact if you don't have your DVD player hooked up via S-Video you probably have it connected via digital Compenent.
Since most uninformed people refer to a red/white/yellow 3-RCA cable as an "RCA cable", you could argue that such an RCA cable includes a composite video signal. The very article you linked to tells us that you need 3 cables (or 3 2-conductor wires bundled together, whatever) to carry a component video signal, so at a minimum a "RCA cable" wouldn't include component video, it would BE component video.
That entire section on there about digital component video does not apply to this discussion. It refers to the fact that stored digital video is saved with that number of bits allocated to the various color components. While I can find a reference to a digital video signal being sent over a 3-RCA cable at
http://www.interfacebus.com/Design_Connector_Video.html you won't find such an interface on any consumer-grade electronics.
If you have your DVD player hooked up with a red/white/yellow 3-RCA cable, you have composite video.
If you have your DVD player hooked up with a S-Video and either red/white or digital audio, you have S-Video
If you have your DVD player hooked up with 3 RCA's for video, and either 2 more RCA's or a digital cable for audio, you have analog component video.
I would not make the assumption either way on composite/component for people not using S-Video - both are very common.
Composite Video
Is analog only baby.
I never claimed it was digital. In fact, I specifically said it was analog.
Seperate Video
Super Video or S-VHS was a tape recording standard.
Before today, I've never seen S-Video refered to as "separate video", and the fact that a Wikipedia article does is nowhere near enough evidence for me to change my mind. The link I posted above to interfacebus.com defines S-Video as Super-Video. I've seen both names used on a few other sites I came across while doing a bit of research before posting this. Suffice it to say, we could both post long lists of links to back up our positions, and we'd still have not gotten anywhere. I don't really care what S-Video stands for, the fact remains that composite video combines everything into 1 signal, S-Video uses 2, and component uses 3, and hence quality improves as you upgrade from composite, to S-Video, to component.
Yes - some devices may have crappy implementations of component video and look better on S-Video. There are a lot of crappy implentations of a lot of things out there - my parents old set-top box from Shaw had something funky with its S-Video output and looked much better over coax (even though that involved taking the video, RF-modulating it, tuning the TV to channel 4, and then re-building the video signal from the RF signal).
And as for your picture - I could care less what "the internet" says - its wrong, and here's another picture explaining why.
