• Title/Summary/Keyword: multiscale edge

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Wavelet Generation and It's Application in Gravity Potential (중력 포텐셜에서의 웨이브렛 생성과 응용)

  • Kim, Sam-Tai;Jin, Hong-Sung;Rim, Hyoung-Rae
    • Journal of the Korean earth science society
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    • v.25 no.2
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    • pp.109-114
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    • 2004
  • A wavelet method is applied to the analysis of gravity potential. One scaling function is proposed to generate wavelet. The scaling function is shown to be replaced to the Green’s function in gravity potential. The upward continuation can be expressed as a wavelet transform i.e. convolution with the scaling function. The scaling factor indicates the height variation. The multiscale edge detection is carried by connecting the local maxima of the wavelet transform at scales. The multiscale edge represents discontinuity of the geological structure. The multiscale edge method is applied to gravity data from Masan and Changwon.

Analysis of Tubular Structures in Medical Imaging

  • Kim, Jin-Woo
    • Journal of information and communication convergence engineering
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    • v.7 no.4
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    • pp.545-550
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    • 2009
  • A method fully utilizing multiscale line filter responses is presented to estimate the point spread function(PSF) of a CT scanner and diameters of small tubular structures based on the PSF. The estimation problem is formulated as a least square fitting of a sequence of multiscale responses obtained at each medical axis point to the precomputed multiscale response curve for the ideal line model. The method was validated through phantom experiments and demonstrated through phantom experiments and demonstrated to accurately measure small-diameter structures which are significantly overestimated by conventional methods based on the full width half maximum(FWHM) and zero-crossing edge detection.

Line-Edge Detection Using New 2-D Wavelet Function (새로운 2-D 웨이브렛 함수를 이용한 라인-에지 검출)

  • Bae Sang-Bum;Kim Nam-Ho
    • Journal of Korea Multimedia Society
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    • v.8 no.2
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    • pp.174-180
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    • 2005
  • Points of sharp variations in image are the most important components when we analyze the features of image. And they include a variety of information about image's shape and location etc. So a lot of researches for detecting edges have been continued. Edge detection operators which were used at the early stage of the research were to utilize relations among neighboring pixels. These methods detect edge at all boundaries, therefore they perform edge detection twice about curves below some width such as line-edge. In the meantime, wavelet transform which is presented as a new technique of signal processing field provides multiscale edge detection and is being applied widely in many fields that analyze edge-like characteristic. Therefore, in this paper we detected line-edge with new 2-D wavelet function which is independent of line's width.

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A Study on Edge Detection using Wavelet in Noise Environment (노이즈 환경에서 웨이브렛을 이용한 에지 검출에 관한 연구)

  • 배상범;김남호
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05b
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    • pp.64-67
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    • 2004
  • Points of sharp variations in images are the most important components when we analyze singularities of images. Therefore a lot of researches for detecting those edges have been continuing even now. However, existing 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, this paper detected image's line-edge elements with 2-D wavelet function, which is independent of line's width, in noise environment.

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A Study on Wavelet-Based Edge Detector (웨이브렛 기반 에지 검출기에 관한 연구)

  • Kim, Nam-Ho;Bae, Sang-Bum
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.2
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    • pp.91-97
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    • 2007
  • Points of sharp variations in signals are the most important factors when analyzing the features of signals. And in the image, edges include diverse information such as the locations, shape and material. There have been a variety of researches on edge detections, among them, methods based on convolution in the spatial domain have been most popular. However at the early stage of the method, if the noise and many kinds of edges exist in the image, it is not easy to separate edges selectively from corrupted images by noise. In meantime, the wavelet transform for multiscale edge detection is being applied widely to analyze the properties of images in various fields. In this paper, we suggest a robust wavelet-based method, which selectively detects line-edge elements from images in the presence of noise.

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Image Enhancement Using Multi-scale Gradients of the Wavelet Transform

  • Okazaki, Hidetoshi;Nakashizuka, Makoto
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.180-183
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    • 2002
  • In this paper, we propose new unsharp masking technique based on the multiscale gradient planes. The unsharp masking technique is implemented as a high-pass filter and improves the sharpness of degraded images. However, the conventional unsharp masking enhances the noise component simultaneously. To reduce the noise influence, we introduce the edge information from the difference of the gradient values between two consecutive scales of the multiscale gradient. The multiscale gradient indicates the presence of image edges as the ratio between the gradients between two different scales by its multiscale nature. The noise reduction of the proposed method does not depend on the variance of images and noises. In experiment, we demonstrate enhancement results for blurred noisy images and compare with the conventional cubic unsharp masking technique.

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Perceptual Fusion of Infrared and Visible Image through Variational Multiscale with Guide Filtering

  • Feng, Xin;Hu, Kaiqun
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1296-1305
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    • 2019
  • To solve the problem of poor noise suppression capability and frequent loss of edge contour and detailed information in current fusion methods, an infrared and visible light image fusion method based on variational multiscale decomposition is proposed. Firstly, the fused images are separately processed through variational multiscale decomposition to obtain texture components and structural components. The method of guided filter is used to carry out the fusion of the texture components of the fused image. In the structural component fusion, a method is proposed to measure the fused weights with phase consistency, sharpness, and brightness comprehensive information. Finally, the texture components of the two images are fused. The structure components are added to obtain the final fused image. The experimental results show that the proposed method displays very good noise robustness, and it also helps realize better fusion quality.

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.

  • PDF

A Triple Residual Multiscale Fully Convolutional Network Model for Multimodal Infant Brain MRI Segmentation

  • Chen, Yunjie;Qin, Yuhang;Jin, Zilong;Fan, Zhiyong;Cai, Mao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.3
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    • pp.962-975
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    • 2020
  • The accurate segmentation of infant brain MR image into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) is very important for early studying of brain growing patterns and morphological changes in neurodevelopmental disorders. Because of inherent myelination and maturation process, the WM and GM of babies (between 6 and 9 months of age) exhibit similar intensity levels in both T1-weighted (T1w) and T2-weighted (T2w) MR images in the isointense phase, which makes brain tissue segmentation very difficult. We propose a deep network architecture based on U-Net, called Triple Residual Multiscale Fully Convolutional Network (TRMFCN), whose structure exists three gates of input and inserts two blocks: residual multiscale block and concatenate block. We solved some difficulties and completed the segmentation task with the model. Our model outperforms the U-Net and some cutting-edge deep networks based on U-Net in evaluation of WM, GM and CSF. The data set we used for training and testing comes from iSeg-2017 challenge (http://iseg2017.web.unc.edu).