TonemappingMethoden

TonemappingMethoden refers to techniques used in computer graphics and image processing to map high dynamic range (HDR) imagery to a lower dynamic range (LDR) display. HDR images contain a much wider range of luminance values than can be accurately represented by standard displays, which typically have a limited dynamic range. Tonemapping algorithms aim to compress this wide range of luminance values into the limited range of the display while preserving as much visual detail and perceptual quality as possible.

Various tonemapping methods exist, each with its own approach to handling the compression. Global tonemapping methods apply a single tone reproduction curve to the entire image. This can sometimes lead to a loss of local contrast or detail in certain areas. Examples include Reinhard's method and Ward's method. Local tonemapping methods, on the other hand, adjust the tone curve based on local image characteristics, such as the surrounding pixel values. This allows for better preservation of local contrast and detail. Examples include Durand and Dorsey's method and Fattal's method.

More advanced methods often combine aspects of both global and local approaches. Some techniques also employ gradient domain processing, where the image is processed in terms of its gradients rather than its absolute luminance values. This can help in preserving the structural information and fine details of the image. The choice of tonemapping method often depends on the specific content of the image and the desired visual outcome, with different methods excelling in different scenarios. The goal is always to create a visually pleasing and informative representation of the original HDR scene.