I have a few different reverse cameras and they all have 4 core wires. Am I correct in believing that if it has 4 wires then 2 will be for the power and the other two will be the composite video? So technically if I can find the + and - power cables then I should be able to connect an RCA connector to the other 2 cables and have it playback via something that can playback composite video? Is there any way to find out which wires will be power related and which will be composite video? possibly by measuring resistance or something maybe?