Definition
Lightness refers to the white, black, or gray shade of a surface. The basic problem is that the light reaching the eye from a given surface, as the product of surface reflectance and illumination, does not specify the reflectance of the surface. A black in sunlight can reflect more light than a white in shadow. No computer program exists that can identify the reflectance of an object in a photo or video. Any possible solution must exploit the context surrounding the object. Anchoring theory proposes to solve the problem by grouping patches of the retinal image into regions of equal illumination, called frameworks, then computing lightness values within each framework using rules of anchoring combined with luminance ratios.
Background
Lightness refers to the perceived shade of white, gray, or black of a surface and is sometimes called perceived reflectance. The reflectance of a surface is the percentage of...
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Gilchrist, A. (2020). Anchoring Theory of Lightness. In: Shamey, R. (eds) Encyclopedia of Color Science and Technology. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-27851-8_263-2
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DOI: https://doi.org/10.1007/978-3-642-27851-8_263-2
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Latest
Anchoring Theory of Lightness- Published:
- 20 August 2020
DOI: https://doi.org/10.1007/978-3-642-27851-8_263-2
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Original
Anchoring Theory of Lightness- Published:
- 30 June 2015
DOI: https://doi.org/10.1007/978-3-642-27851-8_263-1