tonemappausteet

Tonemappausteet, or tone mapping in English, is a technique used in digital image processing and computer graphics to map a set of colors to another set of colors, in order to approximate the appearance of high dynamic range (HDR) imagery on a medium that has a lower dynamic range, such as a standard computer monitor or print. High dynamic range refers to images with a much wider range of luminance and color detail than can typically be displayed by conventional devices.

The process of tonemapping essentially compresses the range of light and shadow in an HDR image to fit within the displayable range of a standard dynamic range (SDR) image. This is achieved through various algorithms that analyze the luminance distribution of the HDR image and apply a non-linear mapping function. Different tonemapping operators exist, each with its own characteristics and suitability for different types of images. Some aim to preserve local contrast, while others focus on global contrast or specific visual styles.

Common tonemapping techniques include global operators, which apply a single mapping function across the entire image, and local operators, which adapt the mapping function based on the surrounding pixels. The goal is to retain as much detail and visual information as possible from the original HDR scene, preventing areas from becoming completely black or blown out white. The effectiveness of tonemapping can significantly influence the perceived realism and aesthetic quality of the final image.