Foggy image–sharpening method with multi-channel polarization information system

Ronghua Li,Junfeng Piao,Qingqing Chu,Kaichun Zhao

doi:10.1177/1687814019834147

Ronghua Li, Junfeng Piao + Show 2 more

Open Access

https://doi.org/10.1177/1687814019834147

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Abstract

This article aims to reduce the influence of heavy fog on the outdoor imaging equipment and to maximally improve the foggy image resolution. It is known that reflected light of the object includes the abundant target polarization information. The foggy image can be restored by these information of the target and the airlight. Therefore, this article introduces a multi-channel polarization information system and defogging algorithm accordingly. The polarization information system provides a necessary solution for the accurate application of a specific algorithm, since it can ensure the accuracy of acquired image information. The key point of the proposed algorithm lies in accurately estimating the parameters in the polarization defogging model. Based on the normal threshold distribution comparison, it can avoid the highlight portion of the non-sky area in the image and accurately estimate the airlight intensity at infinite distance so as to effectively reduce the color distortion of the bright area. The median filtering algorithm is used to obtain the airlight degree of polarization by using three obtained polarization scenes. At last, this article analyzes the experimental results through defogging evaluation indexes and compared the result obtained by this algorithm with others.

Highlights

Haze is the major factor in reducing the effectiveness of visual perception in the outdoor environment
The image enhancement technology is simple and has a wide range of applications, the enhancement effects of haze images captured under different conditions vary
The major contribution of this work is threefold: (1) the construction of a multichannel polarization information system; (2) the implementation of polarization defogging algorithm based on threshold comparison; and (3) image evaluation and analysis after processing with different defogging algorithms

Summary

Introduction

Haze is the major factor in reducing the effectiveness of visual perception in the outdoor environment. Compared with the image-restoration technology, the foggy polarization image sharpening has a wide range of applications In this way, there is no need to obtain more prior information and reduce the tedious degree of the experiment. In view of the great advantages demonstrated by polarization image-sharpening technology and the immaturity of this technology, this article proposed a defogging algorithm based on the atmospheric scattering model.[15] Compared with Schechner et al.[9] and Yoav et al.,[10] there is no human–computer interaction, which improves effectively the processing efficiency. The method based on normal distribution threshold comparison can avoid the highlight area of the non-sky area in the image It can estimate accurately the airlight intensity at an infinite distance and effectively reduce the color distortion of the bright area. In order to reduce the impact of improper values on subsequent algorithms, the algorithm uses the average value of regional pixels

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Findings

Conclusion