The first game footage from the upcoming games, Omega Ruby and Alpha Sapphire was presented on the japanese show Pokémon Get TV and was later uploaded on the official Youtube channel. The video only shows short clips of Groudon and Kyogre summoning their weather effects. This could possibly be part of the opening animation of the games, or maybe a cut scene from the point where the legendary Pokémon are awoken. You can check out the video below: