Wild orcas won't prey upon a human. Cool video! Thanks 
why not? they doesn't know we are kings of creation 
"Killer Whales" aka Orcas, are very social in their behavior and develop separate "colonies".
Individual "colonies" often specialize in particular types of prey. Some colonies feed exclusively on fish, while others hunt marine mammals such as sea lions, seals, walruses or penguins (not to imply that a penguin is a mammal

).
Humans are simply not on their menu and being that they are technically "Dolphins", they are smart enough to recognize when something is not on the menu.
By contrast, a shark will bite into anything that's alive (or not) and close enough to bite into.
(Dang-it! I spend too much time at the Discovery Channel) LOL