My company would like to do an advertisement involving the combination of self-made camera footage with old 8-bit video games along with digital editing. We have speculated about using Duck Hunt, Frogger, Doom, Wolfenstein 3D, among others. The issue we always run into is copyright. We believe Doom would be the best/most likely to be legal.
My question is in regards to copyright laws surrounding id's first person shooter Doom (the original from 1993). After some searching around, Wikipedia informed me that Doom's source code was released in 1997 and the game's engine was placed under the General Public License (GPL) in 1999. It's content license is still proprietary.
We haven't done anything yet, but would like to know if it would be a massive breach of copyright if we used characters and ideas from the game without notifying id. Will Doom's GPL game engine be enough to allow us to do this? Would it be legal to change the characters likeness's and still use them? If so, how much?
Thanks to everyone in advance to looking/commenting. We don't want to break the law!