• Title/Summary/Keyword: 에지 검출 알고리듬

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Segmentation and Recognition of Traffic Signs using Shape Information and Edge Image in Real Image (실영상에서 형태 정보와 에지 영상을 이용한 교통 표지판 영역 추출과 인식)

  • Kwak, Hyun-Wook;Oh,Jun-Taek;Kim, Wook-Hyun
    • The KIPS Transactions:PartB
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    • v.11B no.2
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    • pp.149-158
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    • 2004
  • This study proposes a method for segmentation and recognition of traffic signs using shape information and edge image in real image. It first segments traffic sign candidate regions by connected component algorithm from binary images, obtained by utilizing the RGB color ratio of each pixel in the image, and then extracts actual traffic signs based on their symmetries on X- and Y-axes. Histogram equalization is performed for unsegmented candidate regions caused by low contrast in the image. In the recognition stage, it utilizes shape information including projection profiles on X- and Y-axes, moment, and the number of crossings and distance which concentric circular patterns and 8-directional rays from region center intersects with edges of traffic signs. It finally performs recognition by measuring similarity with the templates in the database. It will be shown from several experimental results that the system is robust to environmental factors, such as light and weather condition.

A Recognition Algorithm for Vehicle Road Lanes and Obstacles Based on Single View Geometric Constitution (단일 시선 기하구조 기반 주행차선 및 장애물 인식 알고리듬)

  • 김정현;송성희;정용배;서경호;김태효
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2004.10a
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    • pp.81-84
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    • 2004
  • 본 논문에서는 1대의 CCD카메라로 주행 중 차선과 선행차량을 인식하고 선행차량까지의 거리를 실시간으로 계측하는 알고리즘을 제시하였다. 도로와 카메라간의 기하구조를 분석하여 사영행렬을 추출하였고, 주행 중 차간 거리를 실시간으로 계측하는데 이용하였다. 또한 차선 인식을 위해서 Hough Transform을 적용하여 처리시간을 단축하였다. 도로상의 장애물은 인식된 주행차선 내로 한정하였고 도로 영상에서 수평에지성분을 구한 후 히스토그램 투영을 적용하여 장애물을 검출하였다. 거리가 점차 멀어질수록 계측오차가 증가함을 볼 수 있었으나 기존의 방법에 비하여 주행 중에 운전자가 장애물을 판단하여 제동을 취할 수 있는 정도의 유효한 오차특성을 보였다.

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Directionally Adaptive Aliasing and Noise Removal Using Dictionary Learning and Space-Frequency Analysis (사전 학습과 공간-주파수 분석을 사용한 방향 적응적 에일리어싱 및 잡음 제거)

  • Chae, Eunjung;Lee, Eunsung;Cheong, Hejin;Paik, Joonki
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.8
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    • pp.87-96
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    • 2014
  • In this paper, we propose a directionally adaptive aliasing and noise removal using dictionary learning based on space-frequency analysis. The proposed aliasing and noise removal algorithm consists of two modules; i) aliasing and noise detection using dictionary learning and analysis of frequency characteristics from the combined wavelet-Fourier transform and ii) aliasing removal with suppressing noise based on the directional shrinkage in the detected regions. The proposed method can preserve the high-frequency details because aliasing and noise region is detected. Experimental results show that the proposed algorithm can efficiently reduce aliasing and noise while minimizing losses of high-frequency details and generation of artifacts comparing with the conventional methods. The proposed algorithm is suitable for various applications such as image resampling, super-resolution image, and robot vision.

Feature Extraction and Image Segmentation of Mechanical Structures from Human Medical Images (의료 영상을 이용한 인체 역학적 구조물 특징 추출 및 영상 분할)

  • 호동수;김성현;김도일;서태석;최보영;김의녕;이진희;이형구
    • Progress in Medical Physics
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    • v.15 no.2
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    • pp.112-119
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    • 2004
  • We tried to build human models based on medical images of live Korean, instead of using standard data of human body structures. Characteristics of mechanical structures of human bodies were obtained from medical images such as CT and MR images. For each constitutional part of mechanical structures CT images were analyzed in terms of gray levels and MR images were analyzed in terms of pulse sequence. Characteristic features of various mechanical structures were extracted from the analyses. Based on the characteristics of each structuring element we peformed image segmentation on CT and MR images. We delineated bones, muscles, ligaments and tendons from CT and MR images using image segmentation or manual drawing. For the image segmentation we compared the edge detection method, region growing method and intensity threshold method and applied an optimal compound of these methods for the best segmentation results. Segmented mechanical structures of the head/neck part were three dimensionally reconstructed.

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Using Optical Flow and HoG for Nighttime PDS (야간 PDS를 위한 광학 흐름과 기울기 방향 히스토그램 이용 방법)

  • Cho, Hi-Tek;Yoo, Hyeon-Joong;Kim, Hyoung-Suk;Hwang, Jeng-Neng
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.7
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    • pp.1556-1567
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    • 2009
  • The death rate of pedestrian in car accidents in Korea is 2.5 times higher than the average of OECD countries'. If a system that can detect pedestrians and send alarm to drivers is built and reduces the rate, it is worth developing such a pedestrian detection system (PDS). Since the accident rate in which pedestrians are involved is higher at nighttime than in daytime, the adoption of nighttime PDS is being standardized by big auto companies. However, they are usually using night visions or multiple sensors, which are usually expensive. In this paper we suggest a method for nighttime PDS using single wide dynamic range (WDR) monochrome camera in visible spectrum band. In our experiments, pedestrians were accurately detected if only most edges of pedestrians could be obtained.

A Study on a 3D Modeling for surface Inspection of a Moving Object (비등속 이동물체의 표면 검사를 위한 3D 모델링 기술에 관한 연구)

  • Ye, Soo-Young;Yi, Young-Youl;Nam, Ki-Gon
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.15-21
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    • 2007
  • We propose a 3D modeling method for surface inspection of non-constant velocity moving object. 1'lie laser lines reflect tile surface curvature. We can acquire 3D surface information by analyzing projected laser lines on object. In this paper, we use multi-line laser to improve the single stripe method and high speed of single frame. Binarization and edge extraction of frame image were proposed for robust laser each line extraction. A new labeling method was used for laser line labeling. We acquired some feature points for image matching from the frame data and juxtaposed the frames data to obtain a 3D shape image. We verified the superiority of proposed method by applying it to inspect container's damages.

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Scleral Diagnostic System Implementation with Color and Blood Vessel Sign Pattern Code Generations (컬러와 혈관징후패턴 코드 생성에 의한 공막진단시스템 구현)

  • Ryu, Kwang Ryol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.12
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    • pp.3029-3034
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    • 2014
  • The paper describes the scleral diagnostic system implementation for human eyes by using the scleral color code and vessels sign pattern code generations. The system is based on the high performance DSP image signal processor, programmable gain control for preprocessing and RISC SD frames storage. RGB image signals are optimized by PGC, the edge image is detected form the gray image converted. The processing algorithms are executed by scleral color code generation and scleral vessels sign pattern code creation for discriminating and matching. The scleral symptomatic color code is generated by YCbCr values at memory map tolerated and the vessel sign pattern code is created by digitizing the 24 clock and 13 ring zones, overlay matching and tolerances. The experimental results for performance are that the system runs 40ms, and the color and pattern for diagnostic errors are around 20% and 24% on average. The system and technique enable a scleral diagnosis with subdividing the patterns and patient database.

Reduction of Radiographic Quantum Noise Using Adaptive Weighted Median Filter (적응성 가중메디안 필터를 이용한 방사선 투과영상의 양자 잡음 제거)

  • Lee, Hoo-Min;Nam, Moon-Hyon
    • Journal of the Korean Society for Nondestructive Testing
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    • v.22 no.5
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    • pp.465-473
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    • 2002
  • Images are easily corrupted by noise during the data transmission, data capture and data processing. A technical method of noise analyzing and adaptive filtering for reducing of quantum noise in radiography is presented. By adjusting the characteristics of the filter according to local statistics around each pixel of the image as moving windowing, it is possible to suppress noise sufficiently while preserve edge and other significant information required in reading. We have proposed adaptive weighted median(AWM) filters based on local statistics. We show two ways of realizing the AWM filters. One is a simple type of AWM filter, whose weights are given by a simple non-linear function of three local characteristics. The other is the AWM filter which is constructed by homogeneous factor(HF). Homogeneous factor(HF) from the quantum noise models that enables the filter to recognize the local structures of the image is introduced, and an algorithm for determining the HF fitted to the detection systems with various inner statistical properties is proposed. We show by the experimented that the performances of proposed method is superior to these of other filters and models in preserving small details and suppressing the noise at homogeneous region. The proposed algorithms were implemented by visual C++ language on a IBM-PC Pentium 550 for testing purposes, the effects and results of the noise filtering were proposed by comparing with images of the other existing filtering methods.