Can I use the 8 cables inside the Cat 6 cable to get the video from 4 CCTV cameras. I find it very bulky to have one big wire for every camera.
I thought if its possible to use 4 pairs to tranfer video via Cat 6 cable.
Use Cat 6 cable with CCTV camera for video output
cat6cctvvideo
Related Solutions
Blue and Blue white are center pair too. If you punch everything down into an RJ 45 jack (ehternet jack) then an RJ 11 (phone jack 2 pair) can plug into an RJ 45 jack and use center 2 pair. Lines up perfectly. Then the line can be used for RJ 45 or RJ 11 purposes. Good Luck!
Thank you @Tetsujin, you solved the problem. To restate your solution using more words: Click on the "Movie Recording" window of QuickTime. Notice the "v" to the right of the red "record" button. Click the "v" and then there is a pulldown menu with three subdivisions: Camera, Microphone, and Quality. 
Best Answer
Probably, with the right adapters, ones that convert unbalanced coax to/from balanced pairs and do the proper impedance conversion. Quality might suffer a hair, but probably not too much. In theory something like this would work, though I'd prefer "active" devices.