Head pasting

Head pasting is an editing technique that involves using cutout faces of individual people or characters, and superimposing them on existing footage in sync with another character's head movements.

Use by Untergangers
Despite being seemingly crude and hastily-made, it is a common practice among FX-based Untergangers who would like to depict characters such as Hitler better than what the original Downfall footage can offer. Headpastes can be done using Sony Vegas (via the Track Motion and/or Event Pan/Crop tools), Adobe After Effects and Adobe Premiere. It can also be done in other editing suites like VideoPad, albeit at a limited extent.

KakashiBallZ and Vzorkic are some of the notable Untergangers to have popularized the use of the technique, with several others making use of it in conjunction with more advanced effects such as rotoscoping and CGI.