I have purchased an outdoor antenna. I need to run a line between the antenna and the TV. To save time, i'd like to use the existing (unused) cable line by attaching the antenna to one of the cables in the image. Can someone with experience please advise which of these cables go to where and which one I can safely connect my antenna to that will track to my TV. We currently only have Centurylink via a phone line (the small brownish cable attached to the PVC pipe on the left of the image).
It looks like you have a common RF 4 way cable splitter, with cable coming into through the green wire and 4 TVs (the other cables). You should look at the splitter closely (is this RF or digital; one in and four out?), and determine if I traced the line correctly.
If this looks like an RF 4 way splitter, and you want to add an antenna (no more "cable TV") you just need to remove the green cable from the splitter and plug in the antenna.
However, if you have a digital (only) splitter, it will not allow the antenna signal to pass through. If you can't be sure what kind of splitter you have, then just try it... nothing will explode if I'm wrong.
If you only have two wires from the antenna, then you need a converter like this: