Digital Compositing for Moving Images

Digital compositing is the process of combining images from a variety of different sources in such a way that they appear to have been shot at the same time under the same lighting conditions with the same camera. The digitally manipulated combination of at least two source images produce an integrated result, which is the most difficult part in the digital compositing process. In particular, the compositor usually attempts to produce images that could have been believably photographed without the use of any post-processing. In other words, they should look real. Even if the elements in the scene are not real, everything in the scene must appear as if they were photographed at the same time, by the same camera. This research discusses a number of different methods to modify a particular sequence of images. The process combined multiple image sequences with basic elements such as over, add, subtract, inside, and outside nodes. Also covered a common issue with color correction and pre-multiplied images for 3D elements compositing Images. Finally, this research reviewed a final sequence images example, in which more advanced and complicated nodes were combined to achieve a complex effects in advanced level. The purpose of this research is to examine a specific process from a professional point of view to analyze and define some terminologies and cover some general issues in computer generated images. In order to understand an essential principle, the researcher also explored some mathematical formulas behind digital compositing. But this research is not intended to be a guide for any specific piece of software. It is intended to give the audience the information needed in order to understand how the digital compositing works and what principles the digital compositing connect with.