• Title/Summary/Keyword: Threshold boundary level

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A Study on Color Image Edge detection Using Adaptive Morphological Wavelet-CNN Algorithm (적응 형태학적 WCNN 알고리즘을 이용한 컬러 영상 에지 검출 연구)

  • Baek, Young-Hyun;Shin, Sung;Moon, Sung-Ryong
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.04a
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    • pp.201-205
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    • 2004
  • The digital color image can be distorted by noise for a transmission or other elements of system. It happens to vague of a boundary side in the division of a color image object, especially, boundary side of an input color image is very important because it can be determined to the division and detection element in pattern recognition. Therefore it is boundary part In this paper, it detects the optimal edge with applying this color image to WCNN algorithm, after it does level up a boundary side of a color image by using the adaptive morphology as the threshold of an input color image. Also, it is used not a conventional fixed mask edge detection method but variable mask method which is cal led a variable BBM. It is confirmed by simulation that the proposed algorithm can be got the batter result edge at the place of closing to each edges and having smoothly curved line.

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An algorithm to acquire the reaction area of skin allergy images

  • Kim, In-Soo;Lee, Myong-Gu;Park, Mignon;Lee, Sang-Bae
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1748-1751
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    • 1991
  • Generally, we can't acquire clear boundary or area from an image having obscure boundary like allergy image by using Sobel or Lapalace operator. Also, when the image not uniform in some part of a image in brightness, there are difficulties to use the global operator such as histogram, for the contour line doesn't have the same grey level. In this paper, we will propose an algorithm to improve those difficulties. The main idea of the algorithm is that we divide the image into many rectangular parts like a chess board, calculate the average of each part, and decide the local threshold for each pixel on the calculated value. In experiment, we can get the contour and area by this algorithm which is much like to the contour and area measured by a doctor. Also, This algorithm has many advantages such as short processing time and little influences of noises and can be used in the robot vision, etc..

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Automated measurement of tool wear using an image processing system

  • Sawai, Nobushige;Song, Joonyeob;Park, Hwayoung
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.311-314
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    • 1995
  • This paper presents a method for measuring tool wear parameters based on two dimensional image information. The tool wear images were obtained from an ITV camera with magnifying and lighting devices, and were analyzed using image processing techniques such as thresholding, noise filtering and boundary tracing. Thresholding was used to transform the captured gray scale image into a binary image for rapid sequential image processing. The threshold level was determined using a novel technique in which the brightness histograms of two concentric windows containing the tool wear image were compared. The use of noise filtering and boundary tracing to reduce the measuring errors was explored. Performance tests of the measurement precision and processing speed revealed that the direct method was highly effective in intermittent tool wear monitoring.

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Change Detection Using Image Differencing Method in Pyeongtaeg City (화상간(畵像間) 차이법(差異法)을 활용한 평택시 지역 지표면(地表面) 변화탐지(變化探知))

  • Rim, Sang-Kyu;Kim, Moo-Sung
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.3
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    • pp.185-195
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    • 2002
  • The purpose of this study is to evaluate and seek the best suitable band and threshold boundary level on the change detection of image differencing method using Landsat TM data(20 May 1987 and 20 May 1993) in Pyeongtaeg City. The change detection images differencing method were evaluated by using normal reference data with an optimal threshold level{$mean{\pm}(SD{\times}T$ value). The normal reference data consisted of positive change{change dark into light in image pattern, that is, it changed arable land(paddy, upland, forest and so on) to artificial area(buildings, vinyl-house and roads, etc)} and negative change(change light into dark in image pattern, that is, it changed artificial area into arable land). As the result, the kappa coefficients of visible bands(D1, D2 and D3) were higher than those of infrared bands(D4, D5 and D7), and than D1 image with 1.0 thresholding and normal reference data was a improved result in the land-surface change detection such as kappa coefficient : 68.4%, overall accuracy : 89.2%, negative change : 6.6%, positive change : 10.6%.

An Automatic Extraction of the Lung Region in X- Rays (흉부방사선 영상의 흉부영역 자동검출에 관한 연구)

  • 김용만;장국현
    • Journal of Biomedical Engineering Research
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    • v.10 no.3
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    • pp.331-342
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    • 1989
  • This paper presents a new algorithm that extracts lung region in X-Rays and enhance.j the region. Comparing to prior algorithms that enhance whole X-Ray image, this algorithm leads more effective results. For this algorithm extracts lung region first, and enhances the lung region excluding parameters of other region. For choosing optimal threshold, we compare OTSU's mothod with the proposed method. We obtain lung boundary using contour following algorithm and Rray level searching method in gray level rescaled image. We Process histogram equalization in lung region and obtain enhanced lung image. By using the proposed algorithm, we obtain lung region effectively in chest X-Ray that need in medical image diagnostic system.

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Adaptive morphological Wavelet-CNN Algorithm for the Color Image Edge detection (컬러 영상 에지 검출을 위한 적응 형태학적 WCNN 알고리즘)

  • Beak, Young-Hyun;Moon, Sung-Rung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.4
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    • pp.473-480
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    • 2004
  • This paper presents a new edge detection algorithm in color image. The proposed Adaptive morphological Wavelet-CNN algorithm is divided into two parts : The Adaptive morpholog and WCNN(Wavelet Cellular Neural Networks). It detects the optimal edge with applying this color image to WCNN algorithm, after it does level up a boundary side of a color image by using the adaptive morphology as the threshold of an input color image. Also, it is used not a conventional fixed mask edge detection method but variable mask method which is called a variable BBM. Finally, to show the feasibility of the proposed algorithm, this paper provides by simulation that the color image consists of 30.

DEVELOPMENT OF AN ORTHOGONAL DOUBLE-IMAGE PROCESSING ALGORITHM TO MEASURE BUBBLE VOLUME IN A TWO-PHASE FLOW

  • Kim, Seong-Jin;Park, Goon-Cherl
    • Nuclear Engineering and Technology
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    • v.39 no.4
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    • pp.313-326
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    • 2007
  • In this paper, an algorithm to reconstruct two orthogonal images into a three-dimensional image is developed in order to measure the bubble size and volume in a two-phase boiling flow. The central-active contour model originally proposed by P. $Szczypi\'{n}ski$ and P. Strumillo is modified to reduce the dependence on the initial reference point and to increase the contour stability. The modified model is then applied to the algorithm to extract the object boundary. This improved central contour model could be applied to obscure objects using a variable threshold value. The extracted boundaries from each image are merged into a three-dimensional image through the developed algorithm. It is shown that the object reconstructed using the developed algorithm is very similar or identical to the real object. Various values such as volume and surface area are calculated for the reconstructed images and the developed algorithm is qualitatively verified using real images from rubber clay experiments and quantitatively verified by simulation using imaginary images. Finally, the developed algorithm is applied to measure the size and volume of vapor bubbles condensing in a subcooled boiling flow.

Prediction of Malodorous Landfill Substances Effect on Ambient Air Quality - A Case Study on Cheongju·Cheongwon Metropolitan Landfill - (매립지 악취가 주변 대기질에 미치는 영향 예측 - 청주청원 광역매립지 사례연구 -)

  • Lee, Sang-Woo
    • Journal of Environmental Impact Assessment
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    • v.21 no.5
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    • pp.695-705
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    • 2012
  • The purpose of this study is to investigate concentration level and characteristics of malodour substances generated from landfill site in C city. Also, it is tried to predict distribution of concentration level using ISCST3 model around landfill site. From the results, it can be confirmed that twelfth-class malodour substances such as ammonia, methyl mercaptan, hydrogen sulfide, dimethyl sulfate, dimethyl disulfate, toluene, acetaldehyde, styrene, propionaldehyde, butylaldehyde, n-Valeraldehyde, xylene were generated from landfill site. The levels of the malodour substances were lower than that of permeable concentration regulated by odor control law in Korea. However, the concentration of malodour substances including methyl mercaptan, hydrogen sulfide, acetaldehyde, and propionaldehyde exceeded threshold limit value(TLV). It was seemed that these substances caused the problem of offensive odor around circumstance of landfill. The concentration of malodour substances was higher in slant than in upper part of landfill. The concentrations of malodour substances measured at night time were shown higher level than those at night time because atmospheric condition was stable at night time. It showed that the concentration of malodour substances were higher in spring. The results of atmospheric diffusion model predicted that tolerance limit level of hydrogen sulfide and methyl mercaptan was detected within nearly 5km from the boundary of landfill.

Iris Recognition using MPEG-7 Homogeneous Texture Descriptor (MPEG-7 Homogeneous Texture 기술자를 이용한 홍채인식)

  • 이종민;한일호;김희율
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.45-48
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    • 2002
  • In this paper, we propose an iris recognition system using Homogeneous Texture descriptor of MPEG-7 standard. The texture of iris is generally used in iris recognition system. We segment the pupil with Hough transform and the boundary of iris with it's gray level difference between the white of the eye. To extract Homogeneous Texture descriptor, this iris image is transformed into polar coordinates. The extracted descriptor is then compared with the reference in DB. If their distance is larger than threshold, they are recognized as different iris. Test results will show that Homogeneous Texture descriptor can be a good measure for iris recognition system.

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Automatic Liver Segmentation of a Contrast Enhanced CT Image Using a Partial Histogram Threshold Algorithm (부분 히스토그램 문턱치 알고리즘을 사용한 조영증강 CT영상의 자동 간 분할)

  • Kyung-Sik Seo;Seung-Jin Park;Jong An Park
    • Journal of Biomedical Engineering Research
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    • v.25 no.3
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    • pp.189-194
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    • 2004
  • Pixel values of contrast enhanced computed tomography (CE-CT) images are randomly changed. Also, the middle liver part has a problem to segregate the liver structure because of similar gray-level values of a pancreas in the abdomen. In this paper, an automatic liver segmentation method using a partial histogram threshold (PHT) algorithm is proposed for overcoming randomness of CE-CT images and removing the pancreas. After histogram transformation, adaptive multi-modal threshold is used to find the range of gray-level values of the liver structure. Also, the PHT algorithm is performed for removing the pancreas. Then, morphological filtering is processed for removing of unnecessary objects and smoothing of the boundary. Four CE-CT slices of eight patients were selected to evaluate the proposed method. As the average of normalized average area of the automatic segmented method II (ASM II) using the PHT and manual segmented method (MSM) are 0.1671 and 0.1711, these two method shows very small differences. Also, the average area error rate between the ASM II and MSM is 6.8339 %. From the results of experiments, the proposed method has similar performance as the MSM by medical Doctor.