Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory
To address the issues of fuzzy scene details, reduced definition, and poor visibility in images captured under non-uniform lighting conditions, this paper presents an algorithm for effectively enhancing such images. Firstly, an adaptive color balance method is employed to address the color differenc...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-08-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/13/17/9535 |
| _version_ | 1797582886022414336 |
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| author | Xiu Ji Shuanghao Guo Hong Zhang Weinan Xu |
| author_facet | Xiu Ji Shuanghao Guo Hong Zhang Weinan Xu |
| author_sort | Xiu Ji |
| collection | DOAJ |
| description | To address the issues of fuzzy scene details, reduced definition, and poor visibility in images captured under non-uniform lighting conditions, this paper presents an algorithm for effectively enhancing such images. Firstly, an adaptive color balance method is employed to address the color differences in low-light images, ensuring a more uniform color distribution and yielding a low-light image with improved color consistency. Subsequently, the image obtained is transformed from the RGB space to the HSV space, wherein the multi-scale Gaussian function is utilized in conjunction with the Retinex theory to accurately extract the lighting components and reflection components. To further enhance the image quality, the lighting components are categorized into high-light areas and low-light areas based on their pixel mean values. The low-light areas undergo improvement through an enhanced adaptive gamma correction algorithm, while the high-light areas are enhanced using the Weber–Fechner law for optimal results. Then, each block area of the image is weighted and fused, leading to its conversion back to the RGB space. And a multi-scale detail enhancement algorithm is utilized to further enhance image details. Through comprehensive experiments comparing various methods based on subjective visual perception and objective quality metrics, the algorithm proposed in this paper convincingly demonstrates its ability to effectively enhance the brightness of non-uniformly illuminated areas. Moreover, the algorithm successfully retains details in high-light regions while minimizing the impact of non-uniform illumination on the overall image quality. |
| first_indexed | 2024-03-10T23:28:53Z |
| format | Article |
| id | doaj.art-ad4b45e9906544cfb180df477451f327 |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-10T23:28:53Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-ad4b45e9906544cfb180df477451f3272023-11-19T07:48:22ZengMDPI AGApplied Sciences2076-34172023-08-011317953510.3390/app13179535Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex TheoryXiu Ji0Shuanghao Guo1Hong Zhang2Weinan Xu3National Local Joint Engineering Research Center for Smart Distribution Grid Measurement and Control with Safety Operation Technology, Changchun Institute of Technology, Changchun 130012, ChinaNational Local Joint Engineering Research Center for Smart Distribution Grid Measurement and Control with Safety Operation Technology, Changchun Institute of Technology, Changchun 130012, ChinaNational Local Joint Engineering Research Center for Smart Distribution Grid Measurement and Control with Safety Operation Technology, Changchun Institute of Technology, Changchun 130012, ChinaSchool of Electrical and Electronic Engineering, Changchun University of Technology, Changchun 130012, ChinaTo address the issues of fuzzy scene details, reduced definition, and poor visibility in images captured under non-uniform lighting conditions, this paper presents an algorithm for effectively enhancing such images. Firstly, an adaptive color balance method is employed to address the color differences in low-light images, ensuring a more uniform color distribution and yielding a low-light image with improved color consistency. Subsequently, the image obtained is transformed from the RGB space to the HSV space, wherein the multi-scale Gaussian function is utilized in conjunction with the Retinex theory to accurately extract the lighting components and reflection components. To further enhance the image quality, the lighting components are categorized into high-light areas and low-light areas based on their pixel mean values. The low-light areas undergo improvement through an enhanced adaptive gamma correction algorithm, while the high-light areas are enhanced using the Weber–Fechner law for optimal results. Then, each block area of the image is weighted and fused, leading to its conversion back to the RGB space. And a multi-scale detail enhancement algorithm is utilized to further enhance image details. Through comprehensive experiments comparing various methods based on subjective visual perception and objective quality metrics, the algorithm proposed in this paper convincingly demonstrates its ability to effectively enhance the brightness of non-uniformly illuminated areas. Moreover, the algorithm successfully retains details in high-light regions while minimizing the impact of non-uniform illumination on the overall image quality.https://www.mdpi.com/2076-3417/13/17/9535low-light imageslight componentgamma correctionweighted fusion |
| spellingShingle | Xiu Ji Shuanghao Guo Hong Zhang Weinan Xu Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory Applied Sciences low-light images light component gamma correction weighted fusion |
| title | Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory |
| title_full | Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory |
| title_fullStr | Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory |
| title_full_unstemmed | Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory |
| title_short | Non-Uniform-Illumination Image Enhancement Algorithm Based on Retinex Theory |
| title_sort | non uniform illumination image enhancement algorithm based on retinex theory |
| topic | low-light images light component gamma correction weighted fusion |
| url | https://www.mdpi.com/2076-3417/13/17/9535 |
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