Abstract:
Due to the nonlinearity of the luminance function
produced by many medical recording devices, the quality of
medical images deteriorates, which creates problems in the visual
research work of physicians. X-rays can be taken as an example.
This article examines methods of improving the contrast of
graphic images methods of improving the quality of X-ray
images. The research was carried out in several stages. Attempts
were made to increase the contrast of several dozen X-ray images
to select the best image brightness using brightness conversion
methods in the MATLAB system. Contrast enhancement was
observed during the experiments, resulting in the selection of a
brightness range corresponding to the visual contrast
enhancement. The selection of variables γ for the selected
brightness range of the image was performed. The possibilities of
the image histogram equalization method were considered. To
obtain the best result before performing gamma correction the
method of X-ray image histogram equalization is suggested. An
enhancement version of this algorithm is presented because of
the comparison. Application of the adaptive histogram
equalization algorithm with contrast limitation provides a visual
effect of improving the contrast of X-ray images. The NIQE and
BRISQUE evaluation functions, which do not use reference
images, are used to objectively quantify the conversion results.
