Share 'Using others footage for the demo showreel?'

Hi guys. I am sure most of you have more knowledge regarding this kind of things. I am working on my Game industry oriented portfolio as a composer/sound designer. The problem is that my first two game titles are still in development and I have not got any footage that I can use as a background for my work. How does it work with using others footage, such a game trailers, available for the publ…