Sangita Sharma Phukan
Compositing may be defined as combining multiple images to create a single image. In visual effects post-production, compositing refers to creating complex images or moving images by combining images from different sources—such as real-world digital video, digitised film, synthetic 3-D imagery, 2-D animations, painted backdrops, digital still photographs, and text.
Elements of compositing
The main elements of compositing consist of selections, copy and paste operations, and positioning of image elements. In particular, we are usually attempting to produce (sequences of) images which could have been believably photographed without the use of any post-processing. Colloquially, it should look ‘real.’ Even if the elements in the scene are obviously not real, (huge insects living inside a giant peach, for example), one must be able to believe that everything in the scene was photographed at the same time, by the same camera.
Today, compositing involves the use of computers. Movies are generally shot on 35 mm film. For compositing, the film has to be digitised with a film scanner. It is then transferred to a computer where it can be edited. The compositors gather all material they need for a scene and then combine the different clips to achieve the result that they need. A technique that greatly facilitates compositing is a blue screen where an object or actor is filmed in front of a solid color screen, usually colored blue or green. During compositing, all areas of a frame with that colour are removed which allows the compositor to place the object or actor in front of a new background.