It's probably a license plate scanner or a car transponder scanner due to how teched up cars have become. It doesn't seem to be a camera due to a lack of a obvious source of energy that cameras love to gobble up and the fact that there doesn't appear to be any obvious changes in the object's casing that would indicate a camera such as a bit of transparent plastic/glass. I think that the two hook like protuberances are antennas, perfect for monitoring car transponders.