Once these images are imported into the system, they can be used just like any other image in LightWave 3D (e.g., as a texture, background, etc.). Debevec and Jitendra Malik at ) or data rendered in LightWave saved in one of the high dynamic range formats. This can be imagery generated from a series of photographs taken at various exposures and composited (see Recovering High Dynamic Range Radiance Maps from Photographs by Paul E. LightWave can utilise high dynamic range detail, as it is generated internally (e.g., in the case of a very bright light) or from data in image files. This may not seem significant at first glance - white is white after all - but, if we look at how LightWave utilizes that data, it becomes very exciting. This means that when LightWave points a light at a surface, while the final rendered pixel may reach only RGB 255, 255, 255 for pure white, internally that pixel may have reached ten times that amount. LightWave, however, calculates all internal data without limits and with IEEE floating-point accuracy. All of these effects can be seen in images captured by devices that do not support high dynamic ranges.īecause computer graphics applications were designed to output to devices that would not understand pixel values above RGB 255, 255, 255, most applications do not provide for any value to exceed these limits. For example, sunlight streaming into a room will bounce off the floor and add a subtle illumination to the walls and ceiling that would otherwise be left dark ( this bouncing of light is known as radiosity). These very bright surfaces can also contribute to the overall lighting of a scene. Some of those artifacts can be seen as blooming areas of brightness, color bleed, luminance spill, lens streaking, and many other visual cues that tell the viewer there is a very bright light source in the scene. When exposed to high dynamic range visuals, such as a sunset or a desert landscape, the lens of a camera will produce some level of artifacting. Video cameras, however, are limited to a fixed range that fits closely to the same 256-step limit. Film can also react to a much wider range. In the real world, the human eye can perceive a much higher range of brightness and color values. See the discussion on radiosity for additional information on high dynamic range images. This means the maximum amount of color or luminance variation an image is allowed is merely 256 steps. Those 256 steps of color represent eight bits and together all three channels make up a 24-bit image. These values typically range from 0 to 255. In computer graphics, color is displayed as a triplet value: red, green and blue.
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