theorising computer-generated imagery (cgi)

Computers have impacted on every area of cinematic production as well as creating new categories in which many animation and cinematic techniques are used. The most influential of these have been video and computer games and interactive multimedia (non-linear and interactive media combining moving image, graphics, sound and text plus information and navigational design.) To date there have been few attempts to theorise computer-generated material with many theorists and creators relying on cannibalising the theories and histories generated for and from other media (see, for example, Brenda Laurel 'Computers as Theatre' -- Aristotelian concept of theatre, Frank Popper -- based in light and kinetic art movements, etc.). Other writers have based their theories on individual creative evolution when working with computer technologies.

Robin King, for example proposes four stages: mimetic, derivative, innovative and emergent. The mimetic stage is characterised by the replication of works originally made in other media such as photography, painting, cinema, etc. The second, derivative, stage involves individuals 'porting their already established aesthetics and ideas to computer platform; as King notes,

"It is perhaps to be expected that an artist will try to extend his or her working methods and stylistic preferences to a new technology or to work within an established stylistic framework."

The innovative stage is reached when the creator demonstrates novel techniques, content or imagery through alterations to the existing computer paradigm -- for example, through repurposing or altering existing software or hardware or creating purpose-built programs. In King's last category, the emergent stage, works are characterised by the unique properties of the media which King sees as being interactivity, simulation and intelligence.

John Lansdown identifies three consecutive approaches to working creatively with computers: tool, medium and intelligent apprentice. In the tool stage the computer is used to continue doing what they have already been doing but with greater efficiency, reliability, speed and accuracy (for example, graphic design). the content remains more or less the same but the conditions of creating it have changed. The medium stage is reached when computers are used to make things that could not have been made before (think of the difference between early cinema with its staged setting and the development of montage cinema of the '20's and '30's). Lansdown's final stage, intelligent apprentice, is reached when there is a symbiosis between individual and machine where each augment each other interactively.

Within the usage of computers to generate animation and imagery for linear media (e.g film and television) such theories have much applicability -- but often individuals and commercial production seem to turn them back to front. For example much early research concentrated on procedural animation whereas later productions have duplicated the look and content of earlier forms -- Who Framed Roger Rabbit, for example, used CGI to create the look of traditional handdrawn cel animation.

computers, animation and cinema

At its birth, the camera drew together threads of Western culture - including the realism of geographic perspective first established with Renaissance painting, the close association of light, vision and truth in western thought, and the ideal of scientific objectivity of the Enlightenment and 19th century. These underpinned the cultural authority that photography was immediately able to claim. So enthusiastically was the realism of photography embraced that the traditional arts were threatened and retaliated by suggesting that the photograph was nothing more than the 'imprint of reality' and so could never be 'an art' as 'art' was dependent on the subjective interpretation and imagination of the artist. The imputation of photographic realism was passed on to the medium of cinema once those photographs were projected and sped up.

Initially, cinema looked to the photography of the streets for its inspiration, but almost immediately two other options became obvious: The first was to use the medium to tell stories, the other to use the medium to counterfeit reality. This quickly led to two distinct but interwoven strands. The stop-motion films of Melieres, for example, led to a cinema of the fantastic, the impossible and eventually to the non-narrative and formalist experiments of filmmakers since the '20s. The storytelling option looked to previous media - opera, theatre, pantomime, the novel. Technical limitations, lack of financial investment encouraged theatre-like productions. Limited sets, long takes, medium to long camera lengths and chronological narratives all mimicked the experience of watching a play. It wasn't until the early 20th century that filmmakers like Eisenstein developed the montage in parallel with developments in the re-invigorated fine arts. He realised that the story could be told in the arrangement of visual but discontinuous images. That the audience did not have to see something from a single viewpoint in which they could logically see every aspect, but could infer action from a series of images from different viewpoints. Time itself became malleable.

Camera-movement, the close-up and point-of-view shot and the development of synched soundtracks rapidly widened the gap between cinema and other media. It developed a language, a textuality, of its own. Cheating with reality was always part of this. So-called classical Hollywood cinema developed the most influential paradigm of camera reality based around montage, shot-matching and continuity. Once 'realism' was was re-located to the structure of the filmic text and the organisation of the viewing experience, it no longer mattered whether individual shots had a direct reverential relationship to real events occuring at a determinate time and place. Cinematic creditability shifted to the movement of the text rather then the photographic moment. Some theorists including Baudrillard and Guy Debord have insisted that this 'camera-reality' has become the defining reality of the 20th century, the reality of the spectacle and the hyper-real.

CGI has been chiefly used to fuse seamlessly with camera reality, to augment rather then displace reality. So strongly has camera reality become fused with our sense of experiential veracity that systems like the Avid and Flame include the possibility to add the artifacts of analogue film to digital media -- speed blur, lens flare, etc. -- to make the digital look likew filmed. A parallel can be drawn with the development of montage which demanded that viewers suspend their identification with the photographic frame and instead form a new relation with the film as a text composed out of multiple shots. This involved finding new ways to negotiate the transitions beytween shots (dissolves, fades, cross-cuts etc). The relationship between the film as an organic unity of discontinuous moments and reality inevitably became more abstract

With digital media this relationship has become more abstract still. It creates a new mise-en-scene, arranging pixels rather than people or sets. Instead of the fragmentation and re-assemblage of the image over time which is the crux of the classical montage, it introduces a new kind of fluid montage within the frame (eg morphing). This has led to a definite impact on the aesthetics and possibilities of cinema. Been argued it has encourage a cinema of impact - big budget special effects films - films which aim to overwhelm the view by sheer scale, velocity and viscerality of the experience. The use of fast editing and a complex visual style (Natural born Killers, Propero's Book, Romeo and Juliet) brings back innovations first made in video and television.

The use of digital media in cinema has led to profound creative changes. Edit lengths have got shorter - it was only 10 years ago that it was received wisdom that the human brain could not pick up intelligible content from a shorter then 2 second cut. There is more experimentation with time; both structurally within narratives, and materially, within the communication of the narrative. Added to this has been the development of increasingly complex and designed imagery. Even the most naturalistic scene can be the result of digital composition of 3D animation -- a studio in LA, a sky in Melbourne enhanced in Darwin, and a location in Russia -- Baz Lehrman's Romeo + Juliet providing a well-known *local* example. And that is without the huge budget multimedia trickery of Jurrassic Park in which animitronics and CGI combine to give a super-real experience which has never existed in reality.

Digital media allows production processes to run parallel, as well as playing an increasing role in pre-visualisation at the production-planning stage. This has been paralleled by an increasing globalisation of production. Digital transmission systems like video fax allow aspects of post-production to be distributed globally by skills, cost and availability rather then the pragmatics of proximity.

CGI is significantly altering the role of the cinematographer by allowing an increasing composite image. The best known and most glamerous use of computers is, of course, in CGI - the spectacular realism of big budget Jurrassic Park etc. However, the bulk of CGI usage is in *invisible* work like wire removal, location dressing, frame repairs, etc.

In the sound area DAT recorders have replaced Nagras as the industry standard. DATs advantages include smaller components, increased production quality, cheap storage and non-linear editing. Because it is easier to create and store alternative versions, DATs have led to an increased exploration of sound as a major component of media and in its own right. Digital sound systems in theatre allow better sound reproduction and greater spatialisation of discrete sounds. Digital non-linear editing systems have replaces the Steenbeck as industry standard. Non-linear access has restored the flexibility that editors had when cutting film, whilst maintaining the advantages of earlier video editing systems - speed, instantly viewable results, etc.

a short history of computer animation

Computer animation has been around as long as computer graphics. The University of Utah, funded by DARPA, was the early pioneer in computer graphics and produced many of the well-known names in graphics as well as most of the important early work in computer graphics.

The seminal work in computer graphics is Ivan Sutherland's SketchPad system. This system animated line drawings on a screen by enforcing constraints in real-time, a form of model-based animation). Also produced from the effort of the University of Utah were some early films on a walking and talking figure, an animated hand and an animated face by such folks as Ed Catmull, Frank Crow, Fred Parke, and Jim Blinn. It has only been recently that this early work in animation has actually been eclipsed.

In the late sixties Chuck Csuri was doing some pioneering work in computer animation in the Computer Graphics Research Group at The Ohio State University. A major feature of the animation that came out of Ohio State in the mid-seventies was real-time video playback from a digital disk. The hardware that took the digital information, uncompressed it on the fly and converted it into a video signal was developed at North Carolina State University under John Staudhammer. In the early 80s, the research group became the Advanced Computing Center for Art and Design and continues to produce computer animation.

Norm Badler , at the University of Pennsylvania, was one of the first researchers addressing the problem of human figure animation. He has continued this research and has established the Center for Human Modeling and Simulation . Jack is a software package developed at the Center which supports the positioning and animation of anthropometrically valid human figures in a virtual world.

Also in the mid-seventies, at Cornell University , the Program for Computer Graphics, under the direction of Don Greenberg, generated some architectural walk-throughs of Cornell's campus. In 1974, the first computer animated film, Hunger, was produced by Rene Jodoin, and directed and animated by Peter Foldes. This effort was a 2 1/2 D system that depended heavily on object interpolation techniques.

In the early days, Computer Graphics (CG) appeared in a variety of movies in which it was used as computer graphics (that is, the CG was not intended to fool the audience into thinking it was anything other than CG). For example, Future World (1976) and Star Wars (1977, Image West) fall into this category. One of the earliest commercial cinematic uses of CGI was in Alien (1979). Most of the graphics, which were produced in Britain, were restricted to shots of the spaceship's computers with the displays being largely textual as characters typed in information or queries and the computer appeared to respond. The only computer-generated imagery was a wireframe contour map of the surface of a planet on which the spaceship appeared to land. Using CGI to represent computer-screens and obviously computer-produced graphics as a way or representing future-ness remains one of the most common usages of CGI.

More recently a more sophisticated example, Lawnmower Man (1992, Xaos, Angel Studios) which has a segment of Hollywood's view of Virtual Reality in it, used CG in the same role. (For an even sillier representation of VR, see the Mad About You VR episode). Tron (1982, MAGI) was a little different. Tron was intended to to demonstrate the full range of visual effects which computers could produce. The CG was still supposed to be computer-like because the action takes place inside a computer, but in this case, it was an integral part of the environment that the actions (and actors) were taking place in. Tron integrated computer animation with live action, but, since the action took place in a computer, the CG didn't have to look realistic (and didn't).

"The technique was simple enough. the actors are dressed in white costumes overlaid with a pattern of black lines, representing computer circuits, and filmed in black limbo. Each frame is blown up into a large black and white transparency that can be reshot on an animation stand. The faces remain human but the figures are reduced to an almost cartoon-like web of lines. Lit from behind they can be made to glow as if illuminated from within ... against a computer-generated background."
(Christopher Finch, 'Creating Movie Magic', 1984)

This was the first time CG was used as an integral part of a movie but in many ways the movie slowed down the deployment of CGI in cinema -- perhaps chiefly because the script was non-existent and the film a box-office disaster. Along the same lines of Tron in using CG to create an 'inside the computer' environment is Reboot (1995, Limelight Ltd./BLT Productions).

One main use of CG has been to replace physical models. In this case, CG is used to create realistic elements which are intermixed with the live action. The Last Star Fighter (1984, Gray Demos' Digital Productions, even the Cray X-MP was in the credits) used computer animation instead of building models for special effects. The action takes place in space as well as on planets; CG was used for the scenes in space and physical models were used for the scenes on a planet and the difference between hte two is rather unsubtle. This was the first time CG was used as part of the live action in which it wasn't supposed to look computer generated. More recently, Apollo 13 (1995, Digital Domain) used CG models of the return vehicle from the mission. In TV-land, special note should go to Babylon 5 (1995, Newtek). Babylon 5 was the first TV show to routinely use CG models as regular features -- with the added attraction that they are Amiga-generated. CG is also used to create 'alien' creatures which are supposed to be realistic (i.e convincing), but don't have to match anything that the audience is familiar with.

More challenging is the use of CG to create realistic models of creatures that are familiar to the audience. Jurassic Park (1993, ILM) was the first to completely integrate use of CG character animation in which the graphics were designed so as to blend in with the live action so that it was difficult to tell what was computer generated and what wasn't. Jumanji (1995, ILM) does the same thing with it's incredible modeling of animals.

Another popular CG technique for special effects is the use of particle systems. One of the best examples is in Star Trek II: The Wrath of Khan (LucasFilm computer division, later ILM) in which a wall of fire sweeps over the surface of a planet. Another example is Lawnmower Man in which a character disintegrates into a swirl of small balls. A more recent example from television is in the opening sequence of Star Trek: Deep Space Nine (1995) to model a comet's tail. Twister also used particle systems to simulate a tornado.

There is another class of movies in which CG plays a role - that of 'hidden special effect' (for lack of a better term). CG can be used to cover up mechanical special effects or to enhance the scene to integrate a mechanical special effect more completely. The first digital blue screen matte extraction was in Willow (ILM). The first wire removal was in Howard the Duck (ILM). In True Lies (1994, Digital Domain), CG was used to erase support wires from suspended actors. In Forest Gump (1994, Digital Domain), CG was used to insert a ping pong ball in a sequence showing an extremely fast action game. In Babe (1995, Rythm & Hues), CG was used to move the mouths of animals and fill in the background uncovered by the movement. In Interview with a Vampire (1994, Digital Domain), CG was used to curl the hair of a woman during the transformation into a vampire. In this case, some of the effect was created using 3D graphics and then integrated into the scene by 2D compositing.

('a short history' is very based on Rick Parent's essay)

other sources

Scott McQuire, 'Crossing the Digital Threshold

Phillip Hayward and Tana Wollen, 'Future Visions; New Technologies of the Screen'

O B Harbison, 'Disappearing through the Skylight'

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