CGI (Computer Generated Imagery)
Visual content created using computer software.
In depth
CGI encompasses everything from basic 2D composites to fully 3D modeled characters and environments. It allows filmmakers to create things that would be impossible or too expensive to film practically.
Example
“The dinosaurs in Jurassic Park were a mix of practical effects and groundbreaking CGI.”
Origin and history
Early CGI in feature film dates to experiments in the 1970s, but the medium's real arrival was the watershed of the 1990s — 'Terminator 2' (1991), 'Jurassic Park' (1993), and 'Toy Story' (1995) collectively proved that computer-generated imagery could deliver photorealistic creatures, seamless integration with live action, and an entire feature rendered in the digital domain. The two decades since have been about pushing detail, scale, and real-time interactivity, with virtual production stages now blending CGI and live photography on set.
Why filmmakers use it
CGI lets filmmakers visualize the impossible at a cost that, for many shots, is now lower than building practical equivalents. Its real craft challenge is integration: matching CGI light, motion blur, and grain to the live plate so the audience never notices the seam. The most respected visual effects work — creatures in 'The Lord of the Rings,' the apes of the 'Planet of the Apes' reboots, the de-aging in 'The Irishman' — succeeds precisely because viewers accept the digital element as part of the world rather than a separate effect.
More examples in cinema
- The fully CGI character of Caesar in the 'Planet of the Apes' trilogy, performed via motion capture by Andy Serkis.
- The volumetric LED stage used for 'The Mandalorian' projects CGI environments behind live actors in real time.
Common confusion
CGI is often blamed for any visual effect that looks unconvincing, even when the actual problem is poor compositing, rushed schedules, or lighting mismatch rather than the technique itself.