EVALUATION AND CORRECTION OF VISUAL CHARACTERISTICS OF IMAGES
Authors:   Kyiv National University of Construction and Architecture, Tereikovska Liudmyla , Tereikovskyi Ihor ,   National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute"
Published: February 2025

Considering the rapid development of image processing technologies and the growing dependence on high-quality visual data, improving the efficiency of image processing is one of the most urgent tasks in the field of computer vision, medical technology and automated control systems, where the accuracy of visual information is critical to ensure safety and efficiency. At the same time, the most important tasks that provide a solution to this problem include the task of evaluating and correcting the brightness and contrast of bitmap images. The subject of the research are models and methods of image processing to modify their visual characteristics. The purpose of the work is to determine the approaches and methods that should be used to evaluate and correct the visual characteristics of images in various conditions of use. The research methodology is based on the theory of digital processing of signals and images and system analysis and provides for the formation of a list of proven approaches and methods for evaluating and correcting the visual characteristics of an image, determining their mathematical support and conducting computer experiments aimed at their verification in various conditions of application. As a result of the conducted research, a list of proven approaches and methods for evaluating and correcting the visual characteristics of the image was determined. It is shown that approaches based on the use of the maximum, minimum, and average values of brightness for the entire image, as well as for its individual areas or color channels, are used to estimate the brightness of the image. Areas of application of approaches to image contrast assessment are shown. The conditions for the expediency of using proven image processing methods for brightness modification have been determined. Threshold processing method – image binarization and segmentation in character recognition and technical quality control. The method of linear transformation - for pre-processing of images, if it is necessary to select individual objects and correct excessively bright or dark areas. The method of logarithmic transformation is for displaying details in the shadows and in light areas at the same time, if it is necessary to increase the contrast of small details when recognizing X-ray and ultrasound images of medical diagnostics. The gamma correction method is used to improve the quality of image display, which is used in pre-processing before they are submitted to recognition tools. Conditions for the feasibility of using proven image processing methods for contrast modification are also defined. The method of linear contrast - to improve the visual quality of the image obtained in conditions of insufficient lighting. The solarization method is used to create dramatic visual effects and to reveal local image features. The partial inverse contrast method is used to highlight objects in a certain range of intensities, which is used to detect local changes in the image texture. It is substantiated that the prospects for further research are related to the development of a methodology for the adaptation of assessment tools and correction of visual characteristics of images to the conditions of use in neural network video stream processing systems in real time.