Image-based lighting is a technique that involves using an image as a light source. The image represents an omni-directional view of the environment of the scene. With image-based lighting, the image itself is treated as a highly detailed light source that surrounds the scene completely. Objects in the scene are illuminated by the content of the image, making it possible to have a very complex lighting environment and/or to simulate a real world setting. Often, these images are produced using a special camera or special photographic techniques, and are recorded in high dynamic range. An example of one such image is shown here (image courtesy of USC Institute for Creative Technologies and Paul Debevec):
These ...