LZX visual cortex - inputting external video - composite vs component

Just some quick notes to remind me (and hopefully help others) about inputting external video into the LZX Visual Cortex. When I first bought this module I didn't understand the difference between composite and component video.

The camera is a pretty old Sony HDR-XR260VE

The yellow input is a standard composite. going into the top "y" input.
This will only give you a black/white luma output.
 To get a full colour input you need to use all 3 component inputs: Y, Pb, Pr.

In Composite video all the video information is combined into a single line level signal that is used in analog television. The video cables do not carry audio but are often paired with audio cables.
In the photo above, the composite is the yellow, and the red & white are the left & right audio (and thus remain unplugged).

In Component video , the video signal is split into two or more component channels. 
Like composite, component-video cables do not carry audio but are often paired with audio cables.
Component video usually refers to analog YP_BP_R component video with sync on luma (Y).  

In the pic above, the green "Y" input is termed Luma for luminance or brightness. 
It also importantly carries the sync signal.
Pb carries the difference between blue and luma (B − Y).
P_R carries the difference between red and luma (R − Y).

YPbPr is the analog version of the YCbCr color space; the two are numerically equivalent but YPbPr is designed for use in analog systems while YCbCr is intended for digital video.  
I have tried plugging a DVD player with YCbCr outputs into my Visual Cortex --- it just doesn't work !

The advantage of using the YPbPr inputs is that the quality of the extracted image is nearly identical to the signal before encoding. S-Video and composite video mix the signals together by means of electronic multiplexing (though S-Video does far better as it gives the whole video bandwith to luma and transmits chroma separately). So if you can use S-Video throughout the whole signal chain do it.

The rear of the Visual Cortex.

In the pic above I've plugged into the Y input a simple CCTV camera. Thus there is only a Luma output.
This is mult'ed into the Castle 000 ADC (analog to digital converter) and its output is passed back into channel B of the Visual Cortex. The Castle Clock VCO is triggering the Visual Cortex.



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