This paper presents a method for designing the illumination in an environment using optimization techniques applied to a radiosity based image synthesis system. An optimization of lighting parameters is performed based on user specified constraints and objectives for the illumination of the environment. The system solves for the "best" possible settings for: light source emissivities, element reflectivities, and spot light directionality parameters so that the design goals, suchastominimize energy or to give the the room an impression of privacy, are met. The system absorbs much of the burden for searching the design space allowing the user to focus on the goals of the illumination design rather than the intricate details of a complete lighting specification. A software implementation is described and some results of using the system are reported.

Realism is often a primary goal in computer graphics imagery, we strive to create images that are perceptually indistinguishable from an actual scene. Rendering systems can now closely approximate the physical distribution of light in an environment. However, physical accuracy does not guarantee that the displayed images will have authentic visual appearance. In recent years the emphasis in realistic image synthesis has begun to shift from the simulation of light in an environment to images that look as real as the physical environment they portray. In other words the computer image should be not only physically correct but also perceptually equivalent to the scene it represents. This implies aspects of the Human Visual System (HVS) must be considered ifrealism is required. Visual perception is employed in many different guises in graphics to achieve authenticity. Certain aspects of the human visual system must be considered to identify the perceptual effects that a realistic rendering system must achieve in order to effectively reproduce a similar visual response to a real scene. This paper outlines the manner in which knowledge about visual perception is increasingly appearing in state-of-the-art realistic image synthesis. This STAR is organised into three sections, each exploring the use of perception in realistic image synthesis, each with slightly different emphasis and