Animation is possible because of a biological phenomenon known as persistence of vision and a psychological phenomenon called phi. An object seen by the human eye remains chemically mapped on the eye's retina for a brief time after viewing. Combined with the human mind's need to conceptually complete a perceived action, this makes it possible for a series of images that are changed very slightly and very rapidly one after another to seemingly blend together into a visual illusion of movement.
Today, computers have taken a great deal of manual labor out of the animation and rendering process, and commercial films like Antz, Toy Story, and the Harry Potter movies have utilized the power of computer animation.
Each Harry Potter film has been a blockbuster hit. The world of magic created by JK Rowling comes alive in every Harry Potter movie. Superb performances by the cast, excellent visual effects, and brilliant screenplays have made the Harry Potter movies timeless masterpieces. However, animation is not just about creating cartoon characters—sometimes the main character is real but interacts with animated characters.
One of the techniques used to create a composite picture is motion capture. Motion-capture digital techniques are being applied to the film industry (and related industries) to create more convincing visualizations of imaginary or composite images. For motion capture, a human actor is dressed in a leotard with integral reflective or magnetic markers. The actor performs the actions that are required, and cameras capture the motion of the reflective markers.
Wide varieties of techniques are used in the computer animation process. These techniques can be grouped into two main classes: two-dimensional (2D) and three-dimensional (3D). Although there is some overlap between the two classes, 2D animation software provides animators with the ability to use computers to carry out the time-consuming repetitive tasks that are needed when building a sequence of frames. 3D animation is far more complex because objects have to be created or rendered in each frame. When an object moves or the relative viewpoint of the observer changes, as is the case when the animator wants to create the appearance of camera movement, the program must regenerate all of the changes in perspective, lighting, shadow, and reflection.
3D computer animation involves the application of various interdisciplinary skills. Technology involves the practical application and use of math and science. Some of the interdisciplinary skills required in animation are language and visual arts skills, problem-solving skills, sociological skills, and technology skills.
The desire for improved physical-based animation tools has grown along with advances in computer animation. Established engineering techniques for simulating and modeling the real world have been modified and applied to computer graphics more frequently over the last few years. For example, take the case of practical animation of liquids. Modeling and animating liquids are pragmatic and make compromises between the care that needs to be taken when simulating non-linear physics and the levels of interaction and control animators require.
All animation studios have to work through the same processes to produce animated films:
- Idea Generation and Development: The first step is the generation of an idea and its development. A member of the studio will sponsor an idea for a film or a product and will take it through a selection procedure. If it's adopted, this idea will be fleshed out with a storyline and some scenes. These are further developed by producing storyboards, which are similar to comic strips and start to capture the look and feel of the movie and many of its characters and scenes. This process is completed by making "reels," video mockups of the cartoon, to see if it can stand by itself. If it does not flow or work, it's back to the drawing board.
- Character Creation and Animation: If the reels meet with success, the art department starts to work on characters, creating 3D computer models and adding animation. They produce backgrounds, sets which have to be dressed, and then scenes can be cut. This means that characters are ready to be animated. Some studios use puppets, and animated movement is added later. One of the most common and popular tools in the animation industry is Maya.
- Voice Recording: Voices are recorded, often with several different cuts, and then a selection of the best fits is made. Music and other sound effects are worked on.
- Rendering: The scenes are polished. Shading, lighting, and illumination are added to give a deep and realistic feel to the animation. Finally, the scenes are "rendered"—all of the layers of technical information are put together to form the frames. Any remaining technical issues are resolved at this stage, and the final film is ready for release.
