Historical Background - Compositing was first developed as a photographic process. Over the years thinking in layers has allowed the arts of film, video, videogames, photography, and design to advance is ways the forefathers of our medium could only dream of.
Interfaces - There are many compositing interfces out there. If you understand the principles of compositing you should be able to translate your knowledge to any compositing package. While we are using and learning the Shake compositing package, we are addressing the principles of compositing in a way which can be interpreted across the board in compositing softwares.
Layers - The operaters with which you place one element over another, applying different maths to achieve the look you want.
Transformations - The operators you use to keyframe the elements into a specific place in the timeline.
Colors - The operations with which you manipulate the RGB pixel colors in the composite to achieve the look you want.
Alpha channel - A greyscale image where white = completely opaque and black = completely transparent. Used to determinte which portions of the element will be visible in the composite.
</i>Premultiplication</i> - The multiplication hre is the RGB channels multiplied by the alpha channel. A premultipliued image will blend over another layer with ease because it has an embedded alpha channel. Images that are not premultiplied require the addition of a matte.
Matte - A created alpha channel for an unpremultiplied image.
Pulling A Matte - Creating an alpha channel for an unpremultiplied image. There are a myriad of approaches to pulling a matte.
Matte Creation in Maya - REassignation of materials to geometry to create a false alpha channel which is applied as a matte.
Using Mattes for Problem Solving - Splitting and layering a single Maya render into different layers according to the needs of the4 composite.
Compositing and Rotoscoping Mattes - Using the tools within shake to pull a matte.
Keying - There are assorted tools used to pull a matte for film or video shot in front of a chroma (blue/green/etc) screen. Keying is the technique of matte creation using these tools.
Filters, Warps, and "Other" - Image manipulation operators.
Text - Creation and animation of text nodes over composited layers.
Rendering - Creation of an image sequence from a Shake Script.