• Title/Summary/Keyword: edge-detection

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Ship Detection Using Edge-Based Segmentation and Histogram of Oriented Gradient with Ship Size Ratio

  • Eum, Hyukmin;Bae, Jaeyun;Yoon, Changyong;Kim, Euntai
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.15 no.4
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    • pp.251-259
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    • 2015
  • In this paper, a ship detection method is proposed; this method uses edge-based segmentation and histogram of oriented gradient (HOG) with the ship size ratio. The proposed method can prevent a marine collision accident by detecting ships at close range. Furthermore, unlike radar, the method can detect ships that have small size and absorb radio waves because it involves the use of a vision-based system. This system performs three operations. First, the foreground is separated from the background and candidates are detected using Sobel edge detection and morphological operations in the edge-based segmentation part. Second, features are extracted by employing HOG descriptors with the ship size ratio from the detected candidate. Finally, a support vector machine (SVM) verifies whether the candidates are ships. The performance of these methods is demonstrated by comparing their results with the results of other segmentation methods using eight-fold cross validation for the experimental results.

A Study on Edge Detection using Grey-level Variation of Mask Image (마스크 내 영상의 휘도 변화를 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.17 no.1
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    • pp.204-209
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    • 2013
  • The image processing has been applied to various fields along with development of visual media. The boundary parts in which brightness of image dramatically changes are important factors in order to analysis characteristics of image because edge contains important information and significant features. A number of researches for detecting these edges have been conducted and conventional edge detection methods using relationship between adjacent pixels are that operation speed is superior, but the edge detection characteristics are insufficient because they use fixed mask without considering gray-level variation. In this paper, the novel algorithm using grey-level variation of image in mask is proposed.

A hybrid deep neural network compression approach enabling edge intelligence for data anomaly detection in smart structural health monitoring systems

  • Tarutal Ghosh Mondal;Jau-Yu Chou;Yuguang Fu;Jianxiao Mao
    • Smart Structures and Systems
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    • v.32 no.3
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    • pp.179-193
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    • 2023
  • This study explores an alternative to the existing centralized process for data anomaly detection in modern Internet of Things (IoT)-based structural health monitoring (SHM) systems. An edge intelligence framework is proposed for the early detection and classification of various data anomalies facilitating quality enhancement of acquired data before transmitting to a central system. State-of-the-art deep neural network pruning techniques are investigated and compared aiming to significantly reduce the network size so that it can run efficiently on resource-constrained edge devices such as wireless smart sensors. Further, depthwise separable convolution (DSC) is invoked, the integration of which with advanced structural pruning methods exhibited superior compression capability. Last but not least, quantization-aware training (QAT) is adopted for faster processing and lower memory and power consumption. The proposed edge intelligence framework will eventually lead to reduced network overload and latency. This will enable intelligent self-adaptation strategies to be employed to timely deal with a faulty sensor, minimizing the wasteful use of power, memory, and other resources in wireless smart sensors, increasing efficiency, and reducing maintenance costs for modern smart SHM systems. This study presents a theoretical foundation for the proposed framework, the validation of which through actual field trials is a scope for future work.

Water Segmentation Based on Morphologic and Edge-enhanced U-Net Using Sentinel-1 SAR Images (형태학적 연산과 경계추출 학습이 강화된 U-Net을 활용한 Sentinel-1 영상 기반 수체탐지)

  • Kim, Hwisong;Kim, Duk-jin;Kim, Junwoo
    • Korean Journal of Remote Sensing
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    • v.38 no.5_2
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    • pp.793-810
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    • 2022
  • Synthetic Aperture Radar (SAR) is considered to be suitable for near real-time inundation monitoring. The distinctly different intensity between water and land makes it adequate for waterbody detection, but the intrinsic speckle noise and variable intensity of SAR images decrease the accuracy of waterbody detection. In this study, we suggest two modules, named 'morphology module' and 'edge-enhanced module', which are the combinations of pooling layers and convolutional layers, improving the accuracy of waterbody detection. The morphology module is composed of min-pooling layers and max-pooling layers, which shows the effect of morphological transformation. The edge-enhanced module is composed of convolution layers, which has the fixed weights of the traditional edge detection algorithm. After comparing the accuracy of various versions of each module for U-Net, we found that the optimal combination is the case that the morphology module of min-pooling and successive layers of min-pooling and max-pooling, and the edge-enhanced module of Scharr filter were the inputs of conv9. This morphologic and edge-enhanced U-Net improved the F1-score by 9.81% than the original U-Net. Qualitative inspection showed that our model has capability of detecting small-sized waterbody and detailed edge of water, which are the distinct advancement of the model presented in this research, compared to the original U-Net.

Comparison of Edge Detection using Linear Rank Tests in Images (영상에서 선형순위검정법을 이용한 에지검출 비교)

  • Lim Dong-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.6 s.38
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    • pp.17-26
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    • 2005
  • In this paper we propose three nonparametric tests such as Wilcoxon test, Median test and Van der Waerden test, based on linear rank statistics for detecting edges in images. The methods used herein are based on detecting changes in gray-levels obtained using an edge-height parameter between two sub-regions in a 5$\times$5 window We compare and analysis the performance of three statistical edge detectors in terms of qualitative measures with the edge maps and objective, quantitative measures.

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Moving Object Edge Extraction from Sequence Image Based on the Structured Edge Matching (구조화된 에지정합을 통한 영상 열에서의 이동물체 에지검출)

  • 안기옥;채옥삼
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.425-428
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    • 2003
  • Recently, the IDS(Intrusion Detection System) using a video camera is an important part of the home security systems which start gaining popularity. However, the video intruder detection has not been widely used in the home surveillance systems due to its unreliable performance in the environment with abrupt illumination change. In this paper, we propose an effective moving edge extraction algorithm from a sequence image. The proposed algorithm extracts edge segments from current image and eliminates the background edge segments by matching them with reference edge list, which is updated at every frame, to find the moving edge segments. The test results show that it can detect the contour of moving object in the noisy environment with abrupt illumination change.

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Real Time On-Road Vehicle Detection with Low-Level Visual Features and Boosted Cascade of Haar-Like Features (미약한 시각 특징과 Haar 유사 특징들의 강화 연결에 의한 도로 상의 실 시간 차량 검출)

  • Adhikari, Shyam Prasad;Yoo, Hyeon-Joong;Kim, Hyong-Suk
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.1
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    • pp.17-21
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    • 2011
  • This paper presents a real- time detection of on-road succeeding vehicles based on low level edge features and a boosted cascade of Haar-like features. At first, the candidate vehicle location in an image is found by low level horizontal edge and symmetry characteristic of vehicle. Then a boosted cascade of the Haar-like features is applied to the initial hypothesized vehicle location to extract the refined vehicle location. The initial hypothesis generation using simple edge features speeds up the whole detection process and the application of a trained cascade on the hypothesized location increases the accuracy of the detection process. Experimental results on real world road scenario with processing speed of up to 27 frames per second for $720{\times}480$ pixel images are presented.

A study on the proceeding direction and obstacle detection by line edge extraction (직선 Edge 추출에 의한 주행방향 및 장애물 검출에 관한 연구)

  • 정준익;최성구;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.97-100
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    • 1996
  • In this paper, we describe an algorithm which estimate road following direction using the vanishing point property and obstacle detection. This method of detecting the lane markers in a set of continuous lane highway images using linear approximation is presented. This algorithm is designed for accurate and robust extraction of this data as well as high processing speed. Also, this algorithm reckon distance and chase about an obstacle. It include four algorithms which are lane prediction, lane extraction, road following parameter estimation and obstacle detection algorithm. High accuracy was proven by quantitative evaluation using simulated images. Both robustness and the practicality of real time video rate processing were then confirmed through experiment using VTR real road images.

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Development of a Drowsiness Detection System using Machine Vision (머신 비젼을 이용한 졸음 감지 시스템 개발)

  • Kang, Su Min;Huh, Kyung Moo
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.4
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    • pp.266-270
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    • 2016
  • In this paper, we propose a technique of drowsiness detection using machine vision. The drowsiness of vehicle driver is often the primary cause of motor vehicle accidents. Therefore, the checking of eye images for detecting drowsiness status of driver is critical for preventing these accidents. In our suggested method, we analyze the changes of histogram and edge of eye region images which are acquired using CCD camera. We developed a drowsiness detection system using the histogram and edge change information. The experimental results show that our proposed method enhances the accuracy of detecting drowsiness nearly to 98%, and can be used for preventing vehicle accidents due to the drowsiness of drivers.

Moving Object Contour Detection Using Spatio-Temporal Edge with a Fixed Camera (고정 카메라에서의 시공간적 경계 정보를 이용한 이동 객체 윤곽선 검출 방법)

  • Kwak, Jae-Ho;Kim, Whoi-Yul
    • Journal of Broadcast Engineering
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    • v.15 no.4
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    • pp.474-486
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    • 2010
  • In this paper, we propose a new method for detection moving object contour using spatial and temporal edge. In general, contour pixels of the moving object are likely present around pixels with high gradient value along the time axis and the spatial axis. Therefore, we can detect the contour of the moving objects by finding pixels which have high gradient value in the time axis and spatial axis. In this paper, we introduce a new computation method, termed as temporal edge, to compute an gradient value along the time axis for any pixel on an image. The temporal edge can be computed using two input gray images at time t and t-2 using the Sobel operator. Temporal edge is utilized to detect a candidate region of the moving object contour and then the detected candidate region is used to extract spatial edge information. The final contour of the moving object is detected using the combination of these two edge information, which are temporal edge and spatial edge, and then the post processing such as a morphological operation and a background edge removing procedure are applied to remove noise regions. The complexity of the proposed method is very low because it dose not use any background scene and high complex operation, therefore it can be applied to real-time applications. Experimental results show that the proposed method outperforms the conventional contour extraction methods in term of processing effort and a ghost effect which is occurred in the case of entropy method.