• 제목/요약/키워드: Edge direction

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The Detection of Rectangular Shape Objects Using Matching Schema

  • Ye, Soo-Young;Choi, Joon-Young;Nam, Ki-Gon
    • Transactions on Electrical and Electronic Materials
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    • v.17 no.6
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    • pp.363-368
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    • 2016
  • Rectangular shape detection plays an important role in many image recognition systems. However, it requires continued research for its improved performance. In this study, we propose a strong rectangular shape detection algorithm, which combines the canny edge and line detection algorithms based on the perpendicularity and parallelism of a rectangle. First, we use the canny edge detection algorithm in order to obtain an image edge map. We then find the edge of the contour by using the connected component and find each edge contour from the edge map by using a DP (douglas-peucker) algorithm, and convert the contour into a polyline segment by using a DP algorithm. Each of the segments is compared with each other to calculate parallelism, whether or not the segment intersects the perpendicularity intersecting corner necessary to detect the rectangular shape. Using the perpendicularity and the parallelism, the four best line segments are selected and whether a determined the rectangular shape about the combination. According to the result of the experiment, the proposed rectangular shape detection algorithm strongly showed the size, location, direction, and color of the various objects. In addition, the proposed algorithm is applied to the license plate detecting and it wants to show the strength of the results.

Overload Measurement and Control of Access Control Channel Based on Hysteresis at Satellite Communication of DAMA (이진영상을 이용한 효율적인 에지 기반의 디인터레이싱 보간 알고리즘)

  • Lee Cheong-Un;Kim Sung-Kwan;Lee Dong-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.8C
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    • pp.801-809
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    • 2005
  • This paper proposes a new algorithm for improving the performance of the spatial filter which is the most important part of deinterlacing methods. The conventional edge-based algorithms are not satisfactory in deciding the exact edge direction which controls the performance of the interpolation. The proposed algorithm much increases the performance of the intrafield interpolation by finding exact edge directions based on the binary image. Edge directions are decided using 15 by 3 local window to find not only more accurate but also many low-angle edge directions. The proposed interpolation method upgrades the visual quality of the image by alleviating the misleading edge directions. Simulation results for various images show that the proposed method provides better performance than the existing methods do.

A Study on Edge Detection for Images Corrupted by AWGN using Modified Weighted Vector (AWGN에 훼손된 영상에서 변형된 가중치 벡터를 이용한 에지검출에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1518-1523
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    • 2012
  • Due to development of visual media in various industrial sectors, the importance of image processing is increasing. Among the various image processing areas, edge detection is utilized widely for various fields such as object recognition, object segmentation, the medical and other industries. Edge includes the critical factors of images like size, direction and location. Then conventional methods such as Sobel, Prewitt, Roberts and Laplacian are proposed to detect edge. However, edge detection property of these methods is declined when they are applied to the image which corrupted by AWGN(Additive White Gaussian Noise). Therefore, an algorithm using modified weighted filter is proposed in this paper and our method has excellent property on edge detection.

Automatic threshold selection for edge detection using a noise estimation scheme and its application (잡음추측을 이용한 자동적인 에지검출 문턱값 선택과 그 응용)

  • 김형수;오승준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.3
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    • pp.553-563
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    • 1996
  • Detecting edges is one of issues with essentialimprotance in the area of image analysis. An edge in an image is a boundary or contour at which a significant change occurs in image intensity. Edge detection has been studied in many addlications such as imagesegmentation, robot vision, and image compression. In this paper, we propose an automatic threshold selection scheme for edge detection and show its application to noise elimination. The scheme suggested here applied statistical properties of the noise estimated from a noisy image to threshold selection. Since a selected threshold value in the scheme depends on not the characgreistic of an orginal image but the statistical feature of added noise, we can remove ad-hoc manners used for selecting the threshold value as well as decide the value theoretically. Furthermore, that shceme can reduce the number of edge pixels either generated or lost by noise. an application of the scheme to noise elimination is shown here. Noise in the input image can be eliminated with considering the direction of each edge pixedl on the edge map obtained by applying the threshold selection scheme proposed in this paper. Achieving significantly improved results in terms of SNR as well as subjective quality, we can claim that the suggested method works well.

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A Study on Edge Detection Algorithm using Grey Level Converting Function (그레이 레벨 변환 함수를 이용한 에지 검출 알고리즘에 관한 연구)

  • Lee, Chang-Young;Hwang, Yeong-Yeun;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.921-923
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    • 2015
  • Edge in the image includes the size, direction and location of objects. The existing detection methods for detecting this edge is a method using Sobel, Prewitt, Roberts and Laplacian, etc. These existing methods use a fixed weighted mask in order to detect the edge and have somewhat insufficient edge detection characteristics. Therefore in this paper, an algorithm that detects the edge by applying the grey level converting function according to the pixel distribution of local mask was proposed.

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A Study on Algorithm of Edge Detection in Mixed Noise Environments (복합잡음 환경에서 에지 검출에 관한 알고리즘에 관한 연구)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.100-103
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    • 2014
  • Currently, edge detection is utilized in various areas. Edge detection is the preprocessing process for image processing in general, and this is a technology that is considered essential for image processing. According, research on this subject is carried out incessantly. Edge has important image related elements such as size, direction and location of the object of an image. Numerous methods were proposed for the detection. Among them, the representative methods are Sobel, Prewitt, Roberts, Laplacian. However, these existing methods are rather lacking when it comes to the edge detection characteristics in case of the image with mixed noise. Therefore, this study presented edge detection method that utilizes median and average values for the elements depending on the size and location of local mask.

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New Adaptive Interpolation Based on Edge Direction extracted from the DCT Coefficient Distribution (DCT 계수 분포를 이용해 추출한 edge 방향성에 기반한 새로운 적응적 보간 기법)

  • Kim, Jaehun;Kim, Kibaek;Jeon, Gwanggil;Jeong, Jechang
    • Journal of Broadcast Engineering
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    • v.18 no.1
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    • pp.10-20
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    • 2013
  • Nowadays, video technology has been successfully improved creating tremendous results. As video technology improve, multimedia devices and demands from users are diversified. Therefore, a video codec used in these devices should support various displays with different resolutions. The technology to generate a higher resolution image from the associated low-resolution image is called interpolation. Interpolation is generally performed in either the spatial domain or the DCT domain. To use the advantages of both domains, we have proposed the new adaptive interpolation algorithm based on edge direction, which adaptively exploits the advantages of both domains. The experimental results demonstrate that our algorithm performs well in terms of PSNR and reduces the blocking artifacts.

Vote Decision-based Deinterlacing Scheme For Directional Error Correction (방향성 오류 교정을 위한 투표 결정 기반의 디인터레이싱 방법)

  • Oh, Sye-Hoon;Lee, Yeo-Song;Ahn, Chang-Beom;Oh, Seoung-Jun
    • Journal of Broadcast Engineering
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    • v.14 no.3
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    • pp.342-356
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    • 2009
  • This paper presents a vote decision-based deinterlacing scheme for false directional error correction(VDD) to convert interlaced signal into non-interlaced signal using only one fields. The VDD using the vote decision goes through four steps process. The first step extracts regions having doubt of false edge using MM-ELA method. In these regions, the edge direction is decided by the majority vote using upper adjacent pixels's information through the second step. But, we still have undecided directions, which will be decided by the majority vote and the directional average decision at the third step. This step preserves the edge directions and minimizes visual degradation. Finally, the last step interpolates undecided pixels using DOI method which can consider the fine edge direction. Although the VDD with hierarchical structure has a high complexity, it can extract delicate edge compared to other pixel-by-pixel or window-by-window deinterlacing algorithms. Simulation results show that it has significantly improved both the subjective and objective qualities of the reconstructed images.

Object Detection Algorithm in Sea Environment Based on Frequency Domain (주파수 도메인에 기반한 해양 물표 검출 알고리즘)

  • Park, Ki-Tae;Jeong, Jong-Myeon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.4
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    • pp.494-499
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    • 2012
  • In this paper, a new method for detecting various objects that can be risks to safety navigation in sea environment is proposed. By analysing Infrared(IR) images obtained from various sea environments, we could find out that object regions include both horizontal and vertical direction edges while background regions of sea surface mainly include vertical direction edges. Therefore, we present an approach to detecting object regions considering horizontal and vertical edges. To this end, in the first step, image enhancement is performed by suppressing noises such as sea glint and complex clutters using a statistical filter. In the second step, a horizontal edge map and a vertical edge map are generated by 1-D Discrete Cosine Transform technique. Then, a combined map integrating the horizontal and the vertical edge maps is generated. In the third step, candidate object regions are detected by a adaptive thresholding method. Finally, exact object regions are extracted by eliminating background and clutter regions based on morphological operation.

A Morphological Study of Dental Arches in Korean Adults (한국인(韓國人) 성인(成人) 치열궁(齒列弓)의 형태학적(形態學的) 연구(硏究))

  • Woo, Sang-Min
    • The Journal of Korean Academy of Prosthodontics
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    • v.8 no.1
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    • pp.30-36
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    • 1968
  • The measurements on the various items, such as arch form, kinds of anterior dental arch, degree of curvature in anterior dental arches, relationship between direction of the disto-incisal edge of the canine and first premolar, and kinds of posterior dental arch in upper dental arches were studied on 311 cases of the Korean adults aged from 20 to 30years. The results were as follows. 1. The commonest type of the upper dental arches was U-type (53.7%), the remaining were O-type (25.4%) and V-type (20.0%). 2. A slight curvature type (71.87%) prevailed against angulated curvature type in upper anterior dental arches. 3. The degree of curvature from $121^{\circ}$ to $160^{\circ}$ in anterior dental arches was common, and the degree of curve of 1-type with on curvature was smaller than 4, 5 type with two curvature. 4. The direction of the disto-incisal edge of canine went between the tip of the buccal cusp and the lingual incline of the buccal cusp of the first premolar in most dental arches and went lingual incline of the buccal cusp of the first premolar in U-type, from buccal cusp to lingual cusp of the first premolar in O-type and were distributed from buccal edge to central groove of the first premolar in V-type. 5. A posterior dental arch with almost straight curvature was common in 60.87%, and 4-type with a half rounded curve from first premolar to second molar was next.

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