Image brightness JND value measurement method based on region of interest and prediction method

Abstract

The invention discloses an image brightness just noticeable difference (JND) value measurement method based on a region of interest. According to the method, an original image is converted into an xyY space, a component Y undergoes linear compression according to different compression coefficients, and the brightness of an original image is reduced so that a set of test images is obtained; then an visual perception experiment is carried out, and at least one test image is selected to serve as a JND critical image; an image brightness JND value based on the region of interest is calculated according to a binarization image of the region of interest of the original image. The invention further discloses an image brightness JND value prediction method based on the region of interest. 0.26 is taken as the brightness JND prediction value of the image based on the region of interest. According to the image brightness JND value measurement method based on the region of interest and the prediction method, parameters of a displayer and especially influences, capable of being noticed by human eyes, of parameters of brightness and the contrast ratio on image brightness can be assessed quantitatively and improved, and accordingly bases are provided for design and researching of display techniques.

Description

technical field [0001] The present invention relates to a method for measuring an image brightness JND (Just Noticeable Difference: just noticeable difference), in particular to a method for measuring an image brightness JND value based on an area of ​​interest. Background technique [0002] In the information age, display technology provides a friendly way of human-computer interaction. Market research shows that display image quality is one of the important determinants for end users to purchase display devices. Since all displayed information is observed by observers through human eyes, people's judgments on image quality are different for different environments and uses. Therefore, the human factor must be considered in the evaluation of display image quality. Although the subjective evaluation method can better reflect the intuitive quality of the image, it is time-consuming and labor-intensive in engineering applications, and in some cases it cannot be used at all, s...

AI Technical Summary

Problems solved by technology

The problem faced by this method is: the content of natural images is complex, while human vision is a very complicated process, and JND is very small difference, which is easily affected by many factors such as the area of ​​interest.

[0005] Existing brightness JND measurement technology is difficult to apply to arbitrary natural images, for example, DICOM [Digital Imaging and Communications in Medicine (DICOM), Standard-PS 3.14-2003 [S], Part 14: Grayscale Standard Display Function, (2003), p21 -27] The standard publishes the human eye's perception threshold of brightness changes under different brightness conditions, but it is carried out under strict observation conditions, and a test chart of uniform color blocks is used instead of a natural image

Xia Jun et al [Just-noticeable-difference of influential factors of subjective images quality, Xia Jun, Qin Shaoling, Liu Lu, Yin Hanchun, Journal of Southeast University (Natural Science Edition) , 36(5), 2006, p695-699] have also done a preliminary study on the JND of luminance, only selected two natural images, and the experimental method used is the paired comparison method, which can only give a rough range of JND of luminance value

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