• Title/Summary/Keyword: Infrared filter

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A Noisy Infrared and Visible Light Image Fusion Algorithm

  • Shen, Yu;Xiang, Keyun;Chen, Xiaopeng;Liu, Cheng
    • Journal of Information Processing Systems
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    • v.17 no.5
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    • pp.1004-1019
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    • 2021
  • To solve the problems of the low image contrast, fuzzy edge details and edge details missing in noisy image fusion, this study proposes a noisy infrared and visible light image fusion algorithm based on non-subsample contourlet transform (NSCT) and an improved bilateral filter, which uses NSCT to decompose an image into a low-frequency component and high-frequency component. High-frequency noise and edge information are mainly distributed in the high-frequency component, and the improved bilateral filtering method is used to process the high-frequency component of two images, filtering the noise of the images and calculating the image detail of the infrared image's high-frequency component. It can extract the edge details of the infrared image and visible image as much as possible by superimposing the high-frequency component of infrared image and visible image. At the same time, edge information is enhanced and the visual effect is clearer. For the fusion rule of low-frequency coefficient, the local area standard variance coefficient method is adopted. At last, we decompose the high- and low-frequency coefficient to obtain the fusion image according to the inverse transformation of NSCT. The fusion results show that the edge, contour, texture and other details are maintained and enhanced while the noise is filtered, and the fusion image with a clear edge is obtained. The algorithm could better filter noise and obtain clear fused images in noisy infrared and visible light image fusion.

Adaptive Nonlinear Filter for Removal of Salt-Pepper Noise in Infrared Image (적외선 영상의 Salt-Pepper 잡음제거를 위한 적응 비선형 필터)

  • Lee, Je-Il;Kim, Sung-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.9
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    • pp.429-434
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    • 2006
  • In this paper, detection based - adaptive windowed nonlinear filter(DB-AWNF) is proposed for removing salt-pepper noise in infrared image. This filter is composed of impulse detector and window-size-variable median filters. Impulse detector checks whether current pixel is impulse or not using range function and nonlinear location estimator. If impulse is detected, current pixel is filtered according to four kinds of local masks by use of median filter. If not, current pixel is delivered to output like identity filter. In Qualitative view, the proposed could have removed heavy corrupted noise up to 30% and reserved the details of image. In quantitative view, PSNR was measured. The proposed could have about 12-31[dB] more improved performance than those of median $(3{\times}3)$ filter and 13-29[dB] more improved performance than those of median $(5{\times}5)$ filter.

Study of Paprika Growth Characteristic on Covering Selective Light Transmitting Filter in Greenhouse (선택적 광 투과에 따른 파프리카 생육특성 연구)

  • Kang, D.H.;Kim, D.E.;Lee, J.W.;Hong, S.J.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.23 no.1
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    • pp.59-66
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    • 2021
  • This study aimed to a basic research for the development of dye-sensitized solar cells that the wavelength band required for crop growth is passed, and the wavelength band that is not necessary for crop growth can be used for the generation of electricity. The transmissivity according to the illuminance was about 10% higher in the Blue filter and the Green filter than in the Red filter, but the transmissivity according to the PPFD was about 10% higher in the Red filter and the Blue filter than in the Green filter. In addition, the greenhouse attached with 30% infrared blocking filter was predicted to have a lower air temperature than other greenhouses, but it was investigated that there was no significant difference. Therefore, it was investigated that the application of the infrared cut filter would not be appropriate in a greenhouse that controls the temperature by opening a window. As a result of investigating, it was found that the Green and Blue filter greenhouses had the severe overgrowth and the stems grew weaker. The fresh weight of paprika in the infrared blocking filter greenhouse was the highest at 678.9g, and the growth of Red filter and the control greenhouses was relatively poor. Photosynthetic rate, amount of transpiration, and stomatal conductivity were the infrared blocking filter and control greenhouse higher than others. On the other hand, the water use efficiency did not show a big difference.

Infrared Target Extraction Using Weighted Information Entropy and Adaptive Opening Filter

  • Bae, Tae Wuk;Kim, Hwi Gang;Kim, Young Choon;Ahn, Sang Ho
    • ETRI Journal
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    • v.37 no.5
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    • pp.1023-1031
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    • 2015
  • In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

Small Target Detection Method Using Bilateral Filter Based on Surrounding Statistical Feature (주위 통계 특성에 기초한 양방향 필터를 이용한 소형 표적 검출 기법)

  • Bae, Tae-Wuk;Kim, Young-Taeg
    • Journal of Korea Multimedia Society
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    • v.16 no.6
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    • pp.756-763
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    • 2013
  • Bilateral filter (BF), functioning by two Gaussian filters, domain and range filter is a nonlinear filter for sharpness enhancement and noise removal. In infrared (IR) small target detection field, the BF is designed by background predictor for predicting background not including small target. For this, the standard deviations of the two Gaussian filters need to be changed adaptively in background and target region of an infrared image. In this paper, the proposed bilateral filter make the standard deviations changed adaptively, using variance feature of mean values of surrounding block neighboring local filter window. And, in case the variance of mean values for surrounding blocks is low for any processed pixel, the pixel is classified to flat background and target region for enhancing background prediction. On the other hand, any pixel with high variance for surrounding blocks is classified to edge region. Small target can be detected by subtracting predicted background from original image. In experimental results, we confirmed that the proposed bilateral filter has superior target detection rate, compared with existing methods.

FPGA-Based Real-Time Multi-Scale Infrared Target Detection on Sky Background

  • Kim, Hun-Ki;Jang, Kyung-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.11
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    • pp.31-38
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    • 2016
  • In this paper, we propose multi-scale infrared target detection algorithm with varied filter size using integral image. Filter based target detection is widely used for small target detection, but it doesn't suit for large target detection depending on the filter size. When there are multi-scale targets on the sky background, detection filter with small filter size can not detect the whole shape of the large targe. In contrast, detection filter with large filter size doesn't suit for small target detection, but also it requires a large amount of processing time. The proposed algorithm integrates the filtering results of varied filter size for the detection of small and large targets. The proposed algorithm has good performance for both small and large target detection. Furthermore, the proposed algorithm requires a less processing time, since it use the integral image to make the mean images with different filter sizes for subtraction between the original image and the respective mean image. In addition, we propose the implementation of real-time embedded system using FPGA.

The Study on Improvement of Thermal Stress Breakage in Infrared Transmissive Glass for Aircraft Searchlight (항공기용 탐조등 적외선 투과 유리의 열응력 파손 현상 개선 연구)

  • Seo, Young-Jin;Jeong, Sang-Gyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.11
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    • pp.332-337
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    • 2018
  • Aircraft searchlights are used in search or rescue missions when performing night missions, and provide infrared light to keep operations in concealment. During aircraft operation, the infrared ray transmission filter glass for generating infrared rays can break, resulting in problems such as loss of concealment ability and maintenance. In this paper, we describe the procedure for testing the operating conditions of the searchlight when the defect occurs and finding the cause of the defect. We also summarize various methods to improve the cause and process of making the improved filter prototype. In addition, we also describe the results of verifying the performance requirements of the searchlight. As a result of the test and verification, the damage of the filter was improved and the improved filter was applied to the aircraft.

Combination of Infrared Light Source and Barrier Filter for Suction Bruise Photography (음압에 의해 생성된 멍 촬영을 위한 적외선 광원과 필터 조합에 관한 연구)

  • Kim, Ju-Eun;Kim, Ji-Yeon;Jeon, So-Young;Kim, Eun-A;Yu, Je-Seol
    • The Journal of the Korea Contents Association
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    • v.16 no.11
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    • pp.693-698
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    • 2016
  • Bruise caused by damages through physical compression and suction is one of evidences that can prove abuse or assault. It is essential for taking photography to prove a crime. Some studies about the Infrared (IR) light source have limitations that only one IR light source and one barrier filter were used. To find the best combination of filters and IR light sources, we produced suction bruise artificially and used three IR light sources and five barrier filters. Consequently, we found that the best combination is using a tungsten lamp and Kodak Wratten #18A barrier filter.

Conversion of Organic Carbon in Food Processing Wastewater to Photosynthetic Biomass in Photo-bioreactors Using Different Light Sources

  • Suwan, Duangkamon;Chitapornpan, Sukhuma;Honda, Ryo;Chiemchaisri, Wilai;Chiemchaisri, Chart
    • Environmental Engineering Research
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    • v.19 no.3
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    • pp.293-298
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    • 2014
  • An anaerobic photosynthetic treatment process utilizing purple non-sulfur photosynthetic bacteria (PNSB) was applied to the recovery of organic carbon from food processing wastewater. PNSB cells, by-product from the treatment, have high nutrition such as proteins and vitamins which are a good alternative for fish feed. Effects of light source on performance of anaerobic photosynthetic process were investigated in this study. Two bench-scale photo-bioreactors were lighted with infrared light emitting diodes (LEDs) and tungsten lamps covered with infrared transmitting filter, respectively, aiming to supply infrared light for photosynthetic bacteria growth. The photo-bioreactors were operated to treat noodle-processing wastewater for 323 days. Hydraulic retention time (HRT) was set as 6 days. Organic removals in the photo-bioreactor lighted with infrared LEDs (91%-95%) was found higher than those in photo-bioreactor with tungsten lamps with filter (79%-83%). Biomass production in a 150 L bench-scale photo-bioreactor was comparable to a 8 L small-scale photo-bioreactor in previous study, due to improvement of light supply efficiency. Application of infrared LEDs could achieve higher treatment performance with advantages in energy efficiency and wavelength specifity.

TRANSFORMATION OF EXTINCTION VALUES NEAR THE K-BAND

  • Kim Sungsoo S.
    • Bulletin of the Korean Space Science Society
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    • 2004.10b
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    • pp.243-246
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    • 2004
  • We calculate theoretical isochrones in a consistent way for five filters near the K-band, K, K', $K_s$, F205W, and F222M. Even when displayed in the same Vega magnitude system, the near-infrared colors of the same isochrone can differ by up to 0.18 mag at its bright end, depending on the filter. We analyze isochrones for several different extinction values, and find that a care is needed when comparing extinction values that are estimated by different filter sets, in particular when comparing those between atmospheric and space filter sets. To alleviate this problem, we present an 'effective extinction law' for each filter set and isochrone model, which describes extinction behaviour of isochrones in the observed color-magnitude diagram.

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