The movies are allowed to be treated as being in the public domain. However, crediting the images to "NASA / SwRI / MSSS / Gerald Eichstädt", appears appropriate. Add your name or data sources to the credit list, whenever you create derived work. Downloading, viewing, distributing the files, as well as creating derived work is on your own risk.
Raw image data: NASA / JPL / SwRI / MSSS
Image and video processing: Gerald Eichstädt
Sound track: Gerald Eichstädt