Image enhancement method in low-illumination environment

Abstract

The invention discloses an image enhancement method in a low-illumination environment. The grayscale values of pixel points in an original low-illumination image concentrated in a relatively narrow low-brightness range are adjusted to be balanced according to a histogram balance principle of the grayscale values of the pixel points in the low-illumination image by adopting an improved image enhancement algorithm based on grayscale-level movement and pixel point grayscale value correction, and the low-illumination image is moved to a relatively high-brightness range. According to a Retinex theory, an irradiation light component of the image subjected to the grayscale value adjustment is filtered out, and a reflected light component is reserved; a real light and shade relationship between the pixel points in the image is found according to a relative light and shade relationship of the grayscale values in the reflected light component; and linear stretching is performed to obtain final adjusted grayscale values of the pixel points of the image. According to the method, the brightness and contrast of the low-illumination image are improved to a certain extent, color enhancement can be realized to a certain extent, local details in the low-illumination image are highlighted, and the intuitive visual quality of the low-illumination image is remarkably improved.

Description

technical field [0001] The invention relates to the technical field of digital image processing, in particular to an image enhancement method in a low-light environment. Background technique [0002] In recent years, with the continuous development of digital image processing methods and processing technologies, a large number of new methods, new theories and new algorithms have emerged, making this field receive extensive attention. As an important part of digital image processing, image enhancement can effectively enhance the visual effect of the image, improve the clarity of the image, adjust the contrast of the image, and better highlight the edge details of the image, thereby improving the overall quality of an image. quality. Therefore, image enhancement technology is widely used and has good development prospects and research value. [0003] In some specific occasions and under certain conditions, it is unavoidable to watch video images in a low-illuminance (0.0001 ...

AI Technical Summary

Problems solved by technology

[0007] When the histogram equalization method is used to process some images, the enhancement effect is sometimes not ideal, so that the gray distribution histogram of the output image is still not the ideal optimal value after equalization, which requires the low-light image enhancement method Do further research and processing in order to improve a relatively ideal low-light image processing method

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