• Title/Summary/Keyword: edge processing

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Real time image processing and measurement of heart parameter using digital subtraction angiography (디지탈 혈관 조영장치를 이용한 실시간 영상처리와 심장파라미터의 측정)

  • 신동익;구본호;박광석;민병구;한만청
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.570-574
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    • 1990
  • Detection of left ventricular boundary for the functional analysis of LV(left ventricle)is obtained using automatic boundary detection algorithm based on dynamic programming method. This scheme reduces the edge searching time and ensures connective edge detection, since it does not require general edge operator, edge thresholding and linking process of other edge. detection methods. The left ventricular diastolic volume and systolic volume and systolic volume were computed after this automatic boundary detection, and these Volume data wm applied to analyze LV ejection fraction.

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Object Tracking for Elimination using LOD Edge Maps Generated from Canny Edge Maps (캐니 에지 맵을 LOD로 변환한 맵을 이용하여 객체 소거를 위한 추적)

  • Jang, Young-Dae;Park, Ji-Hun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.333-336
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    • 2007
  • We propose a simple method for tracking a nonparameterized subject contour in a single video stream with a moving camera and changing background. Then we present a method to eliminate the tracked contour object by replacing with the background scene we get from other frame. Our method consists of two parts: first we track the object using LOD (Level-of-Detail) canny edge maps, then we generate background of each image frame and replace the tracked object in a scene by a background image from other frame that is not occluded by the tracked object. Our tracking method is based on level-of-detail (LOD) modified Canny edge maps and graph-based routing operations on the LOD maps. To reduce side-effects because of irrelevant edges, we start our basic tracking by using strong Canny edges generated from large image intensity gradients of an input image. We get more edge pixels along LOD hierarchy. LOD Canny edge pixels become nodes in routing, and LOD values of adjacent edge pixels determine routing costs between the nodes. We find the best route to follow Canny edge pixels favoring stronger Canny edge pixels. Our accurate tracking is based on reducing effects from irrelevant edges by selecting the stronger edge pixels, thereby relying on the current frame edge pixel as much as possible. This approach is based on computing camera motion. Our experimental results show that our method works nice for moderate camera movement with small object shape changes.

Line-edge Detection using 2-D Wavelet Function in Mixed Noise Environment (혼합된 잡음환경에서 2-D 웨이브렛 함수를 이용한 라인-에지 검출)

  • Bae Sang-Bum;Kim Nam-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.6 no.2
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    • pp.53-58
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    • 2005
  • Points of sharp variations in images are the most important components when we analyze singularities of images. And they include a variety of information about the image's location and shape etc. So a lot of researches for detecting those edges have been continuing even now and at the early stage of the research, edge detection operators used relation among neighborhood pixels. However, such methods do not have excellent performance in the image which exists noise and can not detect edge selectively. In the meantime, the wavelet transform which is presented as a new technique of signal processing field is able to detect multiscale edge and is being applied widely in many fields that analyze singularities such as edge. For this reason, in this paper we detected image's line-edge elements with 2-D wavelet function, which is independent of line's width, in mixed noise environment.

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A Study on Modified Mask for Edge Detection in AWGN Environment (AWGN 환경에서 에지 검출을 위한 변형된 마스크에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.9
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    • pp.2199-2205
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    • 2013
  • In modern society the image processing has been applied to various digital devices such as smartphone, digital camera, and digital TV. In the field of image processing the edge detection is one of the important parts in the image processing procedure. The image edge means point that the pixel value is changed between background and object rapidly, and includes the important information such as magnitude, location, and orientation. The performance of the existing edge detection method is insufficient for the image degraded by AWGN(additive white Gaussian noise) because it detects edges by using small weighted masks. Therefore, in this paper, to detect edge in AWGN environment effectively, we proposed an algorithm that detects edge as calculated gradient of sorting vector which is transformed by estimated mask from new pixel according to each region.

Algorithm for Detecting PSD Boundary Invasion in Subway PSD using Image Processing (영상처리를 이용한 지하철 스크린 도어의 경계선 침범인식 알고리듬 연구)

  • Baek, Woon-Seok;Lee, Ha-Woon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.5
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    • pp.1051-1058
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    • 2018
  • This paper propose image processing algorithm to prevent safety accidents near by subway platform screen door(PSD). First, edges of the subway PSD images are detected and the boundary line between PSD and subway platform is detected to decide people's approach to the PSD using Hough transform. To do this, we draw the boundary line between the PSD and platform, to detect the boundary line and to decide the people's approach to the detected line is completely connected or not. Generally, edge is the basic characteristic of image; thus, edge detection is very important in image processing applications and computer vision area. The conventional edge detection methods such as Roberts, Sobel, Prewitt, and Laplacian etc, which are using a fixed value of mask, and morphological gradient from the structuring element of view and Canny edge detector are widely used. In this paper, we propose the detection algorithm about the people's approach to the subway PSD to prevent the safety accidents by using Canny edge detector and Hough transform and the computer simulation shows the results.

Line feature extraction in a noisy image

  • Lee, Joon-Woong;Oh, Hak-Seo;Kweon, In-So
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10a
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    • pp.137-140
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    • 1996
  • Finding line segments in an intensity image has been one of the most fundamental issues in computer vision. In complex scenes, it is hard to detect the locations of point features. Line features are more robust in providing greater positional accuracy. In this paper we present a robust "line features extraction" algorithm which extracts line feature in a single pass without using any assumptions and constraints. Our algorithm consists of five steps: (1) edge scanning, (2) edge normalization, (3) line-blob extraction, (4) line-feature computation, and (5) line linking. By using edge scanning, the computational complexity due to too many edge pixels is drastically reduced. Edge normalization improves the local quantization error induced from the gradient space partitioning and minimizes perturbations on edge orientation. We also analyze the effects of edge processing, and the least squares-based method and the principal axis-based method on the computation of line orientation. We show its efficiency with some real images.al images.

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Improved Edge Detection Algorithm Using Ant Colony System (개미 군락 시스템을 이용한 개선된 에지 검색 알고리즘)

  • Kim In-Kyeom;Yun Min-Young
    • The KIPS Transactions:PartB
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    • v.13B no.3 s.106
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    • pp.315-322
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    • 2006
  • Ant Colony System(ACS) is easily applicable to the traveling salesman problem(TSP) and it has demonstrated good performance on TSP. Recently, ACS has been emerged as the useful tool for the pattern recognition, feature extraction, and edge detection. The edge detection is wifely utilized in the area of document analysis, character recognition, and face recognition. However, the conventional operator-based edge detection approaches require additional postprocessing steps for the application. In the present study, in order to overcome this shortcoming, we have proposed the new ACS-based edge detection algorithm. The experimental results indicate that this proposed algorithm has the excellent performance in terms of robustness and flexibility.

Edge-Preserving Algorithm for Block Artifact Reduction and Its Pipelined Architecture

  • Vinh, Truong Quang;Kim, Young-Chul
    • ETRI Journal
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    • v.32 no.3
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    • pp.380-389
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    • 2010
  • This paper presents a new edge-protection algorithm and its very large scale integration (VLSI) architecture for block artifact reduction. Unlike previous approaches using block classification, our algorithm utilizes pixel classification to categorize each pixel into one of two classes, namely smooth region and edge region, which are described by the edge-protection maps. Based on these maps, a two-step adaptive filter which includes offset filtering and edge-preserving filtering is used to remove block artifacts. A pipelined VLSI architecture of the proposed deblocking algorithm for HD video processing is also presented in this paper. A memory-reduced architecture for a block buffer is used to optimize memory usage. The architecture of the proposed deblocking filter is verified on FPGA Cyclone II and implemented using the ANAM 0.25 ${\mu}m$ CMOS cell library. Our experimental results show that our proposed algorithm effectively reduces block artifacts while preserving the details. The PSNR performance of our algorithm using pixel classification is better than that of previous algorithms using block classification.

A Study on Edge Detection Method using Modified Directional Masks (변형된 방향성 마스크를 이용한 에지검출 방법에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.11
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    • pp.2779-2785
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    • 2014
  • Edge Detection is a technique that obtains the particular information of the image using the brightness variation of pixel values and utilized for preprocessing in various image processing sectors. The conventional edge detection methods such as Sobel, Prewitt and Roberts are processed by applying the same weighted value to the entire pixels regardless of pixel distrbution and provides somewhat insufficient edge detection results. therefore, this paper has proposed an edge detection method considering the direction and magnitute of pixels by applying a modified directional mask.

Factors Influencing Edge Dendritic Plating of Steel Sheet in the Electro-Galvanizing Line

  • Du-Hwan Jo;Moonjae Kwon;Doojin Paik;Myungsoo Kim
    • Corrosion Science and Technology
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    • v.23 no.3
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    • pp.215-220
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    • 2024
  • Recently, the demand for Zn-Ni electrogalvanized steel sheets for home appliances and automobiles is increasing. Products should have a thick plating (30 to 40 g/m2) on both side with a thin thickness (≤ 0.8 mm) and the highest surface quality. By a high current density operation, current is concentrated in the edge part of the steel sheet, resulting in large surface dent defects due to dendritic plating. This can lead to a low productivity due to low line speed operation. To solve this problem, this study aimed to identify factors influencing dendritic plating. A cylindrical electroplating device was manufactured. Effects of cut edge shape and thickness of steel plate, current density, temperature, flow rate, electrolyte concentration, and pH on dendrite generation of Zn-Ni electroplating were examined. To investigate effect of edge shape of the steel sheet, the steel sheet was manufactured using three processing methods: shearing, polishing after shearing, and laser. Relative effects thickness and cut edge processing methods of the steel plate, current density, temperature, flow rate, electrolyte concentration, and pH of plating solution on dendrite plating were investigated. To prevent dendrite plating, an edge mask was manufactured and its application effect was investigated.