• Title/Summary/Keyword: Fog Removal

Search Result 37, Processing Time 0.025 seconds

Single Image Fog Removal based on JBDC and Pixel-based Transmission Estimation

  • Kim, Jongho
    • International journal of advanced smart convergence
    • /
    • v.9 no.3
    • /
    • pp.118-126
    • /
    • 2020
  • In this paper, we present an effective single image fog removal by using the Joint Bright and Dark Channel (JBDC) and pixel-based transmission estimation to enhance the visibility of outdoor images susceptible to degradation due to weather and environmental conditions. The conventional methods include refinement process of coarse transmission with heavy computational complexity. The proposed transmission estimation reveals excellent edge-preserving performance and does not require the refinement process. We estimate the atmospheric light in pixel-based fashion, which can improve the transmission estimation performance and visual quality of the restored image. Moreover, we propose an adaptive transmission estimation to enhance the visual quality specifically in sky regions. Comprehensive experiments on various fog images show that the proposed method exhibits reduced computational complexity and excellent fog removal performance, compared with the existing methods; thus, it can be applied to various fields including real-time devices.

Fog Collection/Removal System Using a Moss Filter (이끼필터를 이용한 안개 포집/제거 시스템)

  • Oh, Sunjong;Park, Minyong;Kim, Wandoo;Lim, Hyuneui
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.40 no.7
    • /
    • pp.449-455
    • /
    • 2016
  • Fog causes economic losses in transportation. It also results in health problems when it is combined with air pollutants. Considerable research efforts have focused on developing fog removal systems. However, most systems operate themselves after monitoring the fog. Additionally, continuous energy supply and maintenance are required to retain the fog-removal efficiency of the system. This study included the demonstration of a moss filter (a polyolefin mesh interlaced with moss) as a fog-removal method overcoming the limitations of the fog removal system. Three types of mosses with different surface structures were investigated to elucidate the relation between the moisture absorption rate and the structures. Among the different moss types, Hypopterygium japinicum showed the highest efficiency based on the smallest pore diameter and the largest total pore area. The visibilities with the moss filter and the polyolefin mesh were compared to perform the fog removal tests. The moss filter could provide a cost-effective and eco-friendly fog removal system with sustainability.

A Study on Reduction Effect of White Smoke Fog in Urban Detention Basin using a Fog Removal System (안개제거장치를 이용한 도심 저류지 시설에서의 안개 저감 효과 연구)

  • Lee, Kyu Hong;Lee, Sang Woo;Choi, Jun Sung;Lee, Sung Kyun;Park, Jihwan;Park, Seunghee
    • Journal of Korean Society of Disaster and Security
    • /
    • v.11 no.2
    • /
    • pp.69-74
    • /
    • 2018
  • Fog to which environmental impacts are sensitive has a danger to the safety of citizens due to the difficulty in predicting the specific area/time zone. Therefore, we propose a white smoke fog reduction technique using a fog removal device that can remove fog particles directly through dry air and anionic condensation nucleus instead of conventional passive countermeasures. In this study, to verify the effect of reducing fog and the effect of temperature on the white smoke fog which is frequently occurred in the detention basin. As a result, the visible distance of 100m or more was secured within 30 seconds, and it was confirmed that the fog reduction effect is more effective. Also, the lower the temperature, the larger the amount of white smoke fog was. However, the effect of reducing the white smoke fog by temperature was insignificant. Through this experiment, it was possible to verify the reduction effect of the white smoke fog generated in the detention basin through fog removal device.

Effective machine learning-based haze removal technique using haze-related features (안개관련 특징을 이용한 효과적인 머신러닝 기반 안개제거 기법)

  • Lee, Ju-Hee;Kang, Bong-Soon
    • Journal of IKEEE
    • /
    • v.25 no.1
    • /
    • pp.83-87
    • /
    • 2021
  • In harsh environments such as fog or fine dust, the cameras' detection ability for object recognition may significantly decrease. In order to accurately obtain important information even in bad weather, fog removal algorithms are necessarily required. Research has been conducted in various ways, such as computer vision/data-based fog removal technology. In those techniques, estimating the amount of fog through the input image's depth information is an important procedure. In this paper, a linear model is presented under the assumption that the image dark channel dictionary, saturation ∗ value, and sharpness characteristics are linearly related to depth information. The proposed method of haze removal through a linear model shows the superiority of algorithm performance in quantitative numerical evaluation.

Digital Image based Real-time Sea Fog Removal Technique using GPU (GPU를 이용한 영상기반 고속 해무제거 기술)

  • Choi, Woon-sik;Lee, Yoon-hyuk;Seo, Young-ho;Choi, Hyun-jun
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.12
    • /
    • pp.2355-2362
    • /
    • 2016
  • Seg fog removal is an important issue concerned by both computer vision and image processing. Sea fog or haze removal is widely used in lots of fields, such as automatic control system, CCTV, and image recognition. Color image dehazing techniques have been extensively studied, and expecially the dark channel prior(DCP) technique has been widely used. This paper propose a fast and efficient image prior - dark channel prior to remove seg-fog from a single digital image based on the GPU. We implement the basic parallel program and then optimize it to obtain performance acceleration with more than 250 times. While paralleling and the optimizing the algorithm, we improve some parts of the original serial program or basic parallel program according to the characteristics of several steps. The proposed GPU programming algorithm and implementation results may be used with advantages as pre-processing in many systems, such as safe navigation for ship, topographical survey, intelligent vehicles, etc.

Experimental study on the generation of ultrafine-sized dry fog and removal of particulate matter (초미세 크기의 마른 안개 생성과 이를 이용한 미세먼지 제거 연구)

  • Kiwoong Kim
    • Journal of the Korean Society of Visualization
    • /
    • v.22 no.1
    • /
    • pp.34-39
    • /
    • 2024
  • With the fine particulate matter (PM) poses a serious threat to public health and the environment. The ultrafine PM in particular can cause serious problems. This study investigates the effectiveness of a submicron dry fog system in removing fine PM. Two methods are used to create fine dust particles: burning incense and utilizing an aerosol generator. Results indicate that the dry fog system effectively removes fine dust particles, with a removal efficiency of up to 81.9% for PM10 and 61.9% for PM2.5 after 30 minutes of operation. The dry fog, characterized by a mean size of approximately 1.5 ㎛, exhibits superior performance in comparison to traditional water spraying methods, attributed to reduced water consumption and increased contact probability between water droplets and dust particles. Furthermore, experiments with uniform-sized particles which sizes are 1 ㎛ and 2 ㎛ demonstrate the system's capability in removing ultrafine PM. The proposed submicron dry fog system shows promise for mitigating fine dust pollution in various industrial settings, offering advantages such as energy consumption and enhanced safety for workers and equipment.

A LabVIEW-based Video Dehazing using Dark Channel Prior (Dark Channel Prior을 이용한 LabVIEW 기반의 동영상 안개제거)

  • Roh, Chang Su;Kim, Yeon Gyo;Chong, Ui Pil
    • Journal of Korea Multimedia Society
    • /
    • v.20 no.2
    • /
    • pp.101-107
    • /
    • 2017
  • LabVIEW coding for video dehazing was developed. The dark channel prior proposed by K. He was applied to remove fog based on a single image, and K. B. Gibson's median dark channel prior was applied, and implemented in LabVIEW. In other words, we improved the image processing speed by converting the existing fog removal algorithm, dark channel prior, to the LabVIEW system. As a result, we have developed a real-time fog removal system that can be commercialized. Although the existing algorithm has been utilized, since the performance has been verified real - time, it will be highly applicable in academic and industrial fields. In addition, fog removal is performed not only in the entire image but also in the selected area of the partial region. As an application example, we have developed a system that acquires clear video from the long distance by connecting a laptop equipped with LabVIEW SW that was developed in this paper to a 100~300 times zoom telescope.

Technique of Sea-fog Removal base on GPU (GPU 기반의 해무제거 기술)

  • Choi, Woonsik;Ha, Jun;Youn, Woosang;Kwak, Jaemin;Choi, Hyunjun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2015.05a
    • /
    • pp.576-578
    • /
    • 2015
  • This paper propose the help of the secure a clear view and safe navigation of the coastal ship through the sea-fog removal algorithm. Interest in marine accidents and vessel safety has increased in recent Sewol ferry event. According to statistics coastal ship cause of the marine accident when sea fog on the sea did not secure clear view the ship's occur several incidents of collisions between ships and can see that accounts for a high percentage. Algorithm for image exist sea fog is number of studies. but, such studies take up a lot of calculation quantity in the course of performing the algorithm. In this paper, we improve the computational speed of sea fog over the GPU-based technique was removed to suit real-time video. Furthermore, by using GPU, we succeeded in accelerating the simulation 250 times.

  • PDF

Degradation of Fat, Oil, and Grease (FOGs) by Lipase-Producing Bacterium Pseudomonas sp. Strain D2D3

  • Shon, Ho-Kyong;Tian, Dan;Kwon, Dae-Young;Jin, Chang-Suk;Lee, Tae-Jong;Chung, Wook-Jin
    • Journal of Microbiology and Biotechnology
    • /
    • v.12 no.4
    • /
    • pp.583-591
    • /
    • 2002
  • Biodegradation of fat, oil, and grease (FOGs) plays an Important role in wastewater management and water pollution control. However, many industrial food-processing and food restaurants generate FOG-containing waste waters for which there Is no acceptable technology for their pretreatment. To solve these problems, this study evaluated the feasibility of effective FOG-degrading microorganisms on the biodegradation of olive oil and FOG-containing wastewater. Twenty-two strains capable of degrading FOGs were isolated from five FOG-contaminated sites for the evaluation of their FOG degradation capabilities. Among twenty-two strains tested, the lipase-producing Pseudomonas sp. strain D2D3 was selected for actual FOG wastewater treatment. Its biodegradability was performed at 3$0^{\circ}C$ and pH 8. The extent of FOG removal efficiency was varied for each FOG tested, being the highest for olive oil and animal fat (94.5% and 94.4%), and the lowest for safflower oil (62%). The addition of organic nitrogen sources such as yeast extract, soytone, and peptone enhanced the removal efficiency of FOGs, but the addition of the inorganic nitrogen nutrients such as $NH_4$Cl and $(NH_4)_2SO_4$ did not increase. The $KH_2PO_4$ sources in 0.25% to 0.5% concentrations showed more than 90% degradability. As a result, the main pathway for the oxidation of fatty acids results in the removal of two carbon atoms as acetyl-CoA with each reaction sequence: $\beta$-oxidation. Its lipase activity showed 38.5 U/g DCW using the optimal media after 9 h. Real wastewater and FOGs were used for determining the removal efficiency by using Pseudomonas sp. strain D2D3 bioadditive. The degradation by Pseudomonas sp. strain D2D3 was 41% higher than that of the naturally occurring bacteria. This result indicated that the use of isolated Pseudomonas sp. strain D2D3 in a bioaugmentating grease trap or other processes might possibly be sufficient to acclimate biological processes for degrading FOGs.

Real-time Haze Removal Method using Brightness Transformation based on Atmospheric Scatter Coefficient Rate and Local Histogram Equalization (대기 산란 계수 비율 기반의 밝기변환과 지역적 히스토그램 평활화를 이용한 실시간 안개 제거 방법)

  • Lee, Jae-Won;Hong, Sung-Hoon
    • Journal of Korea Multimedia Society
    • /
    • v.19 no.1
    • /
    • pp.10-21
    • /
    • 2016
  • Images taken from outdoor are degraded quality by fog or haze, etc. In this paper, we propose a method that provides the visibility improved images through fog or haze removal. We proposed haze removal method that uses brightness transform based on atmospheric scatter coefficient rate with local histogram equalization. To calculate the transmission rate that indicate fog rate in original image, we use atmospheric scatter coefficient rate based on quadratic equations about haze model. And primary brightness transformed image can be obtained by using the obtained transmission rate. Also we use local histogram equalization with proposed brightness transform for effectively image visibility enhancement. Unlike existing methods, our method can process real-time with stable and effect image visibility enhancement. Proposed method use only the luminance images processed by good performance surveillance systems because it represents the real-time processing is required, black-box, digital camera and multimedia equipment is applicable. Also because it shows good performance only with the luminance images processed, Surveillance systems, black boxes, digital cameras, and multimedia devices etc, that require real-time processing can be applied.