Get random pixel of a selection

Trying to see if it's possible to get the pixel location of any pixel within a selection. The selection could be very irregular (think multiple selections across a layer). Ultimately, I'm trying to develop something that would allow me to see what the predominant color used on a given layer is. My idea is to randomly sample a few pixels with the colorpicker and see if one stands out. It would be OK if there was a mismatch; I am fine to return #000 if a candidate can't be found. But maybe there's a better approach that I am not thinking of? InDesign is more my domain expertise than PS. Any thoughts or ideas appreciated. Whatever I come up with (if anything) should be efficient enough to be run as part of a larger processing script for a folder of complex PSDs. Thanks.