The problem of no-reference measurement of generalized (full integral) contrast of complex (multi-element) monochrome images for objective assessment of their quality is considered in this paper. Different approaches to the quantitative assessment of the generalized contrast of a complex monochrome image on the basis of an analysis of the contrast values of image elements relative to a preset level of adaptation are considered. The task of measuring the contrast of image elements (objects and background) for a preset adaptation level is solved. A new method of measuring the contrast of two image elements for a preset adaptation level using various definitions of the contrast kernel is proposed. New definitions of the weighted and absolute contrast of two image elements for a preset adaptation level are proposed. New definitions of generalized contrast and incomplete integral contrast of a monochrome image for weighted and absolute contrast are proposed. A comparison of proposed and known definitions of generalized contrast and of incomplete integral contrast of monochrome image for weighted and absolute contrast of image elements is carried out.
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