Optimized Contrast Enhancement for Infrared Images Based on Global and Local Histogram Specification

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Bibliographic Details
Title: Optimized Contrast Enhancement for Infrared Images Based on Global and Local Histogram Specification
Authors: Chengwei Liu, Xiubao Sui, Xiaodong Kuang, Yuan Liu, Guohua Gu, Qian Chen
Source: Remote Sensing, Vol 11, Iss 7, p 849 (2019)
Publisher Information: MDPI AG
Publication Year: 2019
Collection: Directory of Open Access Journals: DOAJ Articles
Subject Terms: 2D histogram, histogram specification, optimization equation, contrast enhancement, Science
Description: In this paper, an optimized contrast enhancement method combining global and local enhancement results is proposed to improve the visual quality of infrared images. Global and local contrast enhancement methods have their merits and demerits, respectively. The proposed method utilizes the complementary characteristics of these two methods to achieve noticeable contrast enhancement without artifacts. In our proposed method, the 2D histogram, which contains both global and local gray level distribution characteristics of the original image, is computed first. Then, based on the 2D histogram, the global and local enhanced results are obtained by applying histogram specification globally and locally. Lastly, the enhanced result is computed by solving an optimization equation subjected to global and local constraints. The pixel-wise regularization parameters for the optimization equation are adaptively determined based on the edge information of the original image. Thus, the proposed method is able to enhance the local contrast while preserving the naturalness of the original image. Qualitative and quantitative evaluation results demonstrate that the proposed method outperforms the block-based methods for improving the visual quality of infrared images.
Document Type: article in journal/newspaper
Language: English
Relation: https://www.mdpi.com/2072-4292/11/7/849; https://doaj.org/toc/2072-4292; https://doaj.org/article/f99c7d5df8ab41719a23b44b61a46504
DOI: 10.3390/rs11070849
Availability: https://doi.org/10.3390/rs11070849
https://doaj.org/article/f99c7d5df8ab41719a23b44b61a46504
Accession Number: edsbas.AF64091C
Database: BASE
Description
Abstract:In this paper, an optimized contrast enhancement method combining global and local enhancement results is proposed to improve the visual quality of infrared images. Global and local contrast enhancement methods have their merits and demerits, respectively. The proposed method utilizes the complementary characteristics of these two methods to achieve noticeable contrast enhancement without artifacts. In our proposed method, the 2D histogram, which contains both global and local gray level distribution characteristics of the original image, is computed first. Then, based on the 2D histogram, the global and local enhanced results are obtained by applying histogram specification globally and locally. Lastly, the enhanced result is computed by solving an optimization equation subjected to global and local constraints. The pixel-wise regularization parameters for the optimization equation are adaptively determined based on the edge information of the original image. Thus, the proposed method is able to enhance the local contrast while preserving the naturalness of the original image. Qualitative and quantitative evaluation results demonstrate that the proposed method outperforms the block-based methods for improving the visual quality of infrared images.
DOI:10.3390/rs11070849