Compositing

Much of the editing in CINELERRA-GG involves compositing which is the combining of visual elements from different sources into single images. This includes such things as speeding up and slowing down the video, changing the resolution, creating a split screen, and fading in and out. Compositing operations are done on the timeline and in the Compositor window (canvas) using various operations and other compositing attributes that are available in the Resources window. When CINELERRA-GG is performing a compositing operation it plays back through the compositing engine, but when not, it uses the fastest decoder that it has.

The CINELERRA-GG Community, 2021
https://www.cinelerra-gg.org