Алгоритм и методика автоматизации процедуры оценивания координат цветности элементов изображения бортовых средств индикации в авионике

Abstract

The authors discuss the design of modern on-board equipment for visualization of the air navigation parameters and geo-details (digital district map) with certain requirements to the quality of the visualized information to be displayed. This kind of quality may be characterized in terms of brightness contrast for each color displayed on the screen. In order to ensure stable readability of the image for a pilot, a special procedure should choose chromaticity the coordinates of the image elements. The problem is considered of the research of the avionics on-board indication equipment in order to determine the set of chromaticity coordinate values for the displayed image with the use of automated design tools, which would allow an enhanced visual perception of the image details in the presence of intense external illumination. Various color coding systems used in the on-board indication equipment based on liquid crystal panels (systems of RGB and XY formats) are examined. The calculation of the chromaticity coordinates was based on Maxwell's color mixing triangle by mutual transformations between the elements of XY-plane and decimal codes of RGB-palette, used in the software of the on-board indication equipment. The scheme workstation for the research is proposed, the main components of the developed automated design tools, installed as part of the workstation, are described. The experimental results containing the measures of the brightness levels and estimated brightness contrast values, which were obtained for the given set of colors, are presented. An algorithm for an automated search for a global maximum on the function of two variables, which represents brightness contrast distribution in the chromaticity coordinates plane, is proposed. The decision-making rule approving the use of RGB-codes is the case when the brightness contrast of the test image displayed in any predefined color exceeds two. The results of the research are the methodology and the algorithm of searching the chromaticity coordinate values, which ensure the maximal brightness contrast level and the corresponding values of chromaticity coordinates at the points of maximal contrast.