• Title/Summary/Keyword: Image Edge

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A Deinterlacing Method Based on the Edge Direction Vectors (에지 방향 벡터 기반 디인터레이싱 기법)

  • Lee, Kwang-Bo;Park, Sung-Han
    • 전자공학회논문지 IE
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    • v.45 no.4
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    • pp.47-53
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    • 2008
  • A new intra-field deinterlacing algorithm with edge direction vector (EDV) in the image block is introduced. This proposed filter is suitable to the region with high motion or scene change. We first introduce an EDV, which is computed by Sobel mask used edge map, so that filer resolution of the edge direction can be acquired. The proposed EDV oriented deinterlacing system operates by identifying small pixel variations in five orientations, $26.5^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$, and $153.5^{\circ}$. The EDV values work as inputs of Sobel mask and return edge direction degree and confidence parameters. Based on edge direction degree and confidence parameters the missing pixel is computed. The results of computer simulations demonstrate that the proposed method outperforms a number of intra-field deinterlacing methods in the literature.

An Edge Detection Algorithm using Modified Mask in AWGN Environment (AWGN 환경에서 변형된 마스크를 이용한 에지 검출 알고리즘)

  • Lee, Chang-Young;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.892-894
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    • 2013
  • Edge has been utilized in various application fields with development of technique of digital image processing. In conventional edge detection methods, there are some methods using mask including Sobel, Prewitt, Roberts and Laplacian operator. Those methods are that implement is simple but generates errors of edge detection in images added AWGN(additive white Gaussian noise). Therefore, to compensate the defect of those methods, in this paper, an edge detection algorithm using modified mask is proposed, and it showed superior edge detection property in AWGN.

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Estimation of Real Boundary with Subpixel Accuracy in Digital Imagery (디지털 영상에서 부화소 정밀도의 실제 경계 추정)

  • Kim, Tae-Hyeon;Moon, Young-Shik;Han, Chang-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.8
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    • pp.16-22
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    • 1999
  • In this paper, an efficient algorithm for estimating real edge locations to subpixel values is described. Digital images are acquired by projection into image plane and sampling process. However, most of real edge locations are lost in this process, which causes low measurement accuracy. For accurate measurement, we propose an algorithm which estimates the real boundary between two adjacent pixels in digital imagery, with subpixel accuracy. We first define 1D edge operator based on the moment invariant. To extend it to 2D data, the edge orientation of each pixel is estimated by the LSE(Least Squares Error)line/circle fitting of a set of pixels around edge boundary. Then, using the pixels along the line perpendicular to the estimated edge orientation the real boundary is calculated with subpixel accuracy. Experimental results using real images show that the proposed method is robust in local noise, while maintaining low measurement error.

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Effective Noise Suppression in Edge Region Using Modified Wiener Filter (수정된 Wiener 필터를 사용한 에지 영역에서의 효과적인 잡음 제거)

  • Song Young-Chul
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.52 no.3
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    • pp.173-180
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    • 2003
  • The modified Wiener filtering method is proposed for effective noise suppression in edge region of images corrupted by additive white gaussian noise. Although the pixels classified as a edge region in the conventional Wiener filter have lots of noise components, the conventional Wiener filler cannot remove noise effectively due to the preserving of edges. To reduce noise well in edge region, we modify filter coefficients of the conventional Wiener filter The modified filter coefficients increase in noise suppression effect In edge region, while they preserve edges for strong edge region. From simulation $(256{\time}256$ size, 256 graylevel images) filtered images by the proposed method show much improved subjective image quality with some improved peak signal-to-noise ratio compared to those by the conventional Wiener filtering.

Combining an Edge-Based Method and a Direct Method for Robust 3D Object Tracking

  • Lomaliza, Jean-Pierre;Park, Hanhoon
    • Journal of Korea Multimedia Society
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    • v.24 no.2
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    • pp.167-177
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    • 2021
  • In the field of augmented reality, edge-based methods have been popularly used in tracking textureless 3D objects. However, edge-based methods are inherently vulnerable to cluttered backgrounds. Another way to track textureless or poorly-textured 3D objects is to directly align image intensity of 3D object between consecutive frames. Although the direct methods enable more reliable and stable tracking compared to using local features such as edges, they are more sensitive to occlusion and less accurate than the edge-based methods. Therefore, we propose a method that combines an edge-based method and a direct method to leverage the advantages from each approach. Experimental results show that the proposed method is much robust to both fast camera (or object) movements and occlusion while still working in real time at a frame rate of 18 Hz. The tracking success rate and tracking accuracy were improved by up to 84% and 1.4 pixels, respectively, compared to using the edge-based method or the direct method solely.

A Study on Variable Block Matching Algorithm Using Edge Information of Differential Image (차영상의 윤곽정보를 이용한 가변 블록 정합 알고리즘에 관한 연구)

  • 권병헌;안정길;황병원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.4
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    • pp.639-648
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    • 1994
  • This paper presents a new block matching algorithm in estimation of motion information that is important technology in compressing interframe. In estimation of motion information, we find differential image using two successive frame image in order to find required real time processing and accurate moving vector, the binary image is made of edge and find more accurate moving vectors by application quadtree method to parts including many moving according to this activity. The computer simulation results show that increased PSNR and reduced computation time.

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Median lifting optimization for lossy edge-dominant image compression

  • Quan, Do;Ho, Yo-Sung
    • IEIE Transactions on Smart Processing and Computing
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    • v.2 no.1
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    • pp.1-10
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    • 2013
  • In JPEG2000, the Cohen-Daubechies-Feauveau (CDF) 9/7-tap wavelet filter is implemented using the conventional lifting scheme. On the other hand, this wavelet filter has two problems: the filter coefficients remain complex, and the conventional lifting scheme does not consider the image edges in the coding process. This paper proposes an effective lifting scheme to solve these problems. For this purpose, optimal 9/7-tap wavelet filters were designed in two steps. In the first step, the appropriate filter coefficients were selected. In the second step, a median operator was employed to consider the image edges. The experimental results with the median lifting scheme and the combination of filter optimization with the median lifting show that the proposed methods outperform the well-known CDF 9/7-tap wavelet filter of JPEG2000 on the edge-dominant images.

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The enhancement of medical image using edge-based histogram modification (에지 기반 히스토그램 평활화를 이용한 의료 영상의 개선)

  • 김경민;문윤식;박중조;정순원;박귀태
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.12
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    • pp.1603-1613
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    • 1995
  • The goal of enhancement is to improve the perceptual aspect and visual appearance of images for human viewers. The objectives of image enhancement vary according to its specific application and an image enhancement algorithms used for a specific objective may not be accepted in some other applications. In this paper we review some of conventional enhancement techniques, such as global histogram equalization(GHE), local histogram equalization(LHE), clipped histogram equalization(CHE). We also describe some modified version of these algorithms. The proposed method is to detect detail information. We distinquish edge from nonedge and apply histigram equalization respectively. Simulation results demonstrate the performance of the proposed method for medical image.

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Object Recognition Using the Edge Orientation Histogram and Improved Multi-Layer Neural Network

  • Kang, Myung-A
    • International Journal of Advanced Culture Technology
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    • v.6 no.3
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    • pp.142-150
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    • 2018
  • This paper describes the algorithm that lowers the dimension, maintains the object recognition and significantly reduces the eigenspace configuration time by combining the edge orientation histogram and principle component analysis. By using the detected object region as a recognition input image, in this paper the object recognition method combined with principle component analysis and the multi-layer network which is one of the intelligent classification was suggested and its performance was evaluated. As a pre-processing algorithm of input object image, this method computes the eigenspace through principle component analysis and expresses the training images with it as a fundamental vector. Each image takes the set of weights for the fundamental vector as a feature vector and it reduces the dimension of image at the same time, and then the object recognition is performed by inputting the multi-layer neural network.

Pyramid Image Coding Using Projection (투영을 이용한 피라미드 영상 부호화)

  • 원용관;김준식;박래홍
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.5
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    • pp.90-102
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    • 1993
  • In this paper, we propose a prgressive image transmission technique using hierarchical pyramid data structure which is constructed based on the projection data of an image. To construct hierarchical Gaussian pyramids, we first divide an image into 4$\times$4 subblocks and generate the projection data of each block along the horizontal, vertical, diagonal, and antidiagonal directions. Among images reconstructed by backprojecting the projection data along a single direction, the one giving the minimum distortion is selected. The Gaussian pyramid is recursively generated by the proposed algorithm and the proposed Gaussian images are shown to preserve edge information well. Also, based on the projection concept a new transmission scheme of the lowest Laplacian plane is presented. Computer simulation shows that the quantitative performance of the proposed pyramid coding technique using projection concept is similar to those of the conventional methods with transmission rate reduced by 0.1 ~ 0.2 bpp and its subjective performance is shown to be better due to the edge preserving property of a projection operation.

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