• 제목/요약/키워드: Small object detection

검색결과 184건 처리시간 0.032초

Ensemble Deep Network for Dense Vehicle Detection in Large Image

  • Yu, Jae-Hyoung;Han, Youngjoon;Kim, JongKuk;Hahn, Hernsoo
    • 한국컴퓨터정보학회논문지
    • /
    • 제26권1호
    • /
    • pp.45-55
    • /
    • 2021
  • 본 논문은 고해상도를 가지는 영상에서 겹쳐져있는 소형 물체를 효과적으로 검출하고 추적하는 알고리즘을 제안한다. Coarse to Fine 방식을 기본으로 하는 두 개의 Deep-Learning Network을 앙상블 형태로 구성하여 차량이 존재할 위치를 미리 판단하고 서브영역으로 선택한 이미지로부터 차량을 정확하게 검출한다. Coarse 단계에서는 서로 다른 다수의 Deep-Learning Network 에 대한 각각의 결과로 Voting Space를 생성한다. 각 Voting Space 의 조합을 통해 Voting Map을 만들고 차량이 존재할 위치를 선택한다. Fine 단계에서는 Coarse 단계에서 선택된 영역을 기준으로 서브영역을 추출하고 해당 영역을 최종 Deep-Learning Network 에 입력한다. 서브 영역은 Voting Map을 이용하여 영상에서의 높이에 적합한 크기의 동적 윈도우를 생성함으로써 정의되며, 본 논문에서는 원거리에서 근거리로 접근하는 도로의 이미지를 대상으로 미리 계산된 매핑테이블을 적용하였다. 각 서브 영역 간 이동하는 차량의 동일성 판단은 검출된 영역의 하단 중심점에 대한 근접성을 기반으로 하였으며, 이를 통해 이동하는 차량의 정보를 트래킹 하였다. 실제 주야간 도로 CCTV를 통해 획득한 실시간 영상에서 처리 속도 및 검출 성능을 비교 실험하여 제안한 알고리즘을 평가하였다.

주기성 배경을 위한 개선된 MOG 알고리즘 (Improved MOG Algorithm for Periodic Background)

  • 정용석;오정수
    • 한국정보통신학회논문지
    • /
    • 제17권10호
    • /
    • pp.2419-2424
    • /
    • 2013
  • 기존 MOG (Mixture of Gaussian) 알고리즘에서 배경 결정을 위한 작은 임계치는 주기적인 배경에서 배경 인식 지연을 발생시키고, 큰 임계치는 고정 배경에서 지나가는 객체를 배경으로 인식하게 한다. 본 논문은 적응적인 임계치를 이용한 개선된 MOG 알고리즘을 제안한다. 제안된 알고리즘은 MOG 알고리즘의 주도적인 배경 모델에서 가중치 변화를 단 장기적으로 평가하고, 배경을 정적 배경과 주기성 배경으로 분류하여 그들에 적절한 임계치를 설정한다. 실험결과들은 제안된 알고리즘이 정적 배경에서 기존 알고리즘과 등등한 성능을 유지하면서 주기성 배경에서 배경인식 지연의 최대 프레임수를 137에서 4로 줄여주는 것을 보여주고 있다.

다중크기와 다중객체의 실시간 얼굴 검출과 머리 자세 추정을 위한 심층 신경망 (Multi-Scale, Multi-Object and Real-Time Face Detection and Head Pose Estimation Using Deep Neural Networks)

  • 안병태;최동걸;권인소
    • 로봇학회논문지
    • /
    • 제12권3호
    • /
    • pp.313-321
    • /
    • 2017
  • One of the most frequently performed tasks in human-robot interaction (HRI), intelligent vehicles, and security systems is face related applications such as face recognition, facial expression recognition, driver state monitoring, and gaze estimation. In these applications, accurate head pose estimation is an important issue. However, conventional methods have been lacking in accuracy, robustness or processing speed in practical use. In this paper, we propose a novel method for estimating head pose with a monocular camera. The proposed algorithm is based on a deep neural network for multi-task learning using a small grayscale image. This network jointly detects multi-view faces and estimates head pose in hard environmental conditions such as illumination change and large pose change. The proposed framework quantitatively and qualitatively outperforms the state-of-the-art method with an average head pose mean error of less than $4.5^{\circ}$ in real-time.

Development of a Hovering Robot System for Calamity Observation

  • Kang, M.S.;Park, S.;Lee, H.G.;Won, D.H.;Kim, T.J.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2005년도 ICCAS
    • /
    • pp.580-585
    • /
    • 2005
  • A QRT(Quad-Rotor Type) hovering robot system is developed for quick detection and observation of the circumstances under calamity environment such as indoor fire spots. The UAV(Unmanned Aerial Vehicle) is equipped with four propellers driven by each electric motor, an embedded controller using a DSP, INS(Inertial Navigation System) using 3-axis rate gyros, a CCD camera with wireless communication transmitter for observation, and an ultrasonic range sensor for height control. The developed hovering robot shows stable flying performances under the adoption of RIC(Robust Internal-loop Compensator) based disturbance compensation and the vision based localization method. The UAV can also avoid obstacles using eight IR and four ultrasonic range sensors. The VTOL(Vertical Take-Off and Landing) flying object flies into indoor fire spots and sends the images captured by the CCD camera to the operator. This kind of small-sized UAV can be widely used in various calamity observation fields without danger of human beings under harmful environment.

  • PDF

워터쉐드 알고리즘을 이용한 지능형 비디오 영상 분할 시스템 (An Intelligent Video Image Segmentation System using Watershed Algorithm)

  • 양황규
    • 한국전자통신학회논문지
    • /
    • 제5권3호
    • /
    • pp.309-314
    • /
    • 2010
  • 본 논문에서는 인터넷상에서의 지능형 감시 카메라 시스템(Intelligent Security Camera: ISC)을 제안한다. ISC 방법은 워터쉐드 알고리즘에 기반하여 카메라에 입력된 영상을 분할하는 단계와 skin-color model을 사용하여 얼굴의 후보지역을 탐지하는 단계, 그리고 마지막으로 SVM(Support Vector Machine)을 사용하여 얼굴 후보영역에서 얼굴을 검증하는 단계로 구성되어 있다. Skin-color Model을 이용하여 찾아진 얼굴후보 영역으로부터 웨이블렛 변환계수들을 추출한다. 웨이블렛 변환계수들을 SVM의 입력으로 하여 실제 얼굴영역을 검증한다. SVM의 입력으로 실험결과에서 제안된 방법이 감시시스템, 화상회의 시스템과 같은 얼굴을 인식 추적하는 시스템에 적용될 수 있음을 보인다.

건설현장 근로자의 안전모 착용 여부 검출을 위한 컴퓨터 비전 기반 딥러닝 알고리즘의 적용 (Application of Deep Learning Algorithm for Detecting Construction Workers Wearing Safety Helmet Using Computer Vision)

  • 김명호;신성우;서용윤
    • 한국안전학회지
    • /
    • 제34권6호
    • /
    • pp.29-37
    • /
    • 2019
  • Since construction sites are exposed to outdoor environments, working conditions are significantly dangerous. Thus, wearing of the personal protective equipments such as safety helmet is very important for worker safety. However, construction workers are often wearing-off the helmet as inconvenient and uncomportable. As a result, a small mistake may lead to serious accident. For this, checking of wearing safety helmet is important task to safety managers in field. However, due to the limited time and manpower, the checking can not be executed for every individual worker spread over a large construction site. Therefore, if an automatic checking system is provided, field safety management should be performed more effectively and efficiently. In this study, applicability of deep learning based computer vision technology is investigated for automatic checking of wearing safety helmet in construction sites. Faster R-CNN deep learning algorithm for object detection and classification is employed to develop the automatic checking model. Digital camera images captured in real construction site are used to validate the proposed model. Based on the results, it is concluded that the proposed model may effectively be used for automatic checking of wearing safety helmet in construction site.

이미지 기반의 특징점 정보를 이용한 제품 검색 서비스에 관한 연구 (A Study on Product Search Service using Feature Point Information based on Image)

  • 김석수
    • 융합정보논문지
    • /
    • 제9권9호
    • /
    • pp.20-26
    • /
    • 2019
  • ICT 기술의 발전과 스마트폰 보급의 활성화로 온라인 마켓을 통해 다양한 제품을 구매하는 구매 서비스가 활성화되고 있다. 특히 보관 및 배송 기술의 발전으로 인하여 보관기관이 짧은 식자재의 경우도 온라인을 통해 구매가 가능함으로써 오프라인 판매만을 수행하는 상가의 경우 매출이 감소되고 있는 추세이다. 따라서 본 논문에서는 기존 오프라인 판매만 수행이 가능한 소규모 상가에서 전문적인 판매 지식 및 판매망이 없어도 구매 서비스를 통해 광고 효과 및 주문, 배달이 가능한 통합 솔루션을 제안한다. 제안하는 시스템은 사용자가 원하는 제품에 대한 이미지 검색을 통해 효율적으로 제품에 대한 정보를 카테고리별로 볼 수 있으며, 이로 인해 등록된 제품 판매처가 추가적인 광고가 없어도 효율적으로 판매가 가능하다는 장점이 있다.

Experimental Research of Piece-Mold Casting: Gilt-Bronze Pensive Bodhisattva

  • Yun, Yong-Hyun;Cho, Nam-Chul;Doh, Jung-Mann
    • 보존과학회지
    • /
    • 제37권4호
    • /
    • pp.340-356
    • /
    • 2021
  • We have tried the experimental research of lost-wax casting to reconstruct Gilt-Bronze Pensive Bodhisattva; preliminary and reconstruction experiment based on ancient texts. Main object to reconstruct is Korean National Treasure No.83, Gilt-Bronze Pensive Bodhisattva (Maitreya), then we measure alloy ratio and casting method based on the scientific analysis. Other impurities were removed from the base metal components(copper : tin : lead) and their ratio was set to 95.5 : 6.5 : 3 where the ratios for tin and lead were increased by 2.5% each. The piece-mold casting method was used, and piece-mold casting experiments were carried out twice in this study but supplementary research on piece-mold casting was necessary. The microstructure was confirmed to be typical cast microstructure and the component analysis result was similar to that of the prior study. Analysis of the chemical composition is confirmed to copper, tin, lead, and zinc, and the chemical composition of the matrix was 87.8%Cu-7.5%Sn-2.7%Pb-2.1%Zn, and similar to previous experimental research. Also resulted in the detection of small impurity in Zn. Analysis of the mould revealed that the mould was fabricated by adding quartz and organic matter for structural stability, fire resistance, and air permeability. We expect that our research will contribute to provide base data for advanced researches in future.

Establishment and Application of a Femtosecond-laser Two-photon-polymerization Additive-manufacturing System

  • Li, Shanggeng;Zhang, Shuai;Xie, Mengmeng;Li, Jing;Li, Ning;Yin, Qiang;He, Zhibing;Zhang, Lin
    • Current Optics and Photonics
    • /
    • 제6권4호
    • /
    • pp.381-391
    • /
    • 2022
  • Two-photon-polymerization additive-manufacturing systems feature high resolution and precision. However, there are few reports on specific methods and possible problems concerning the use of small lasers to independently build such platforms. In this paper, a femtosecond-laser two-photon-polymerization additive-manufacturing system containing an optical unit, control unit, monitoring unit, and testing unit is built using a miniature femtosecond laser, with a detailed building process and corresponding control software that is developed independently. This system has integrated functions of light-spot detection, interface searching, micro-/nanomanufacturing, and performance testing. In addition, possible problems in the processes of platform establishment, resin preparation, and actual polymerization for two-photon-polymerization additive manufacturing are explained specifically, and the causes of these problems analyzed. Moreover, the impacts of different power levels and scanning speeds on the degree of polymerization are compared, and the influence of the magnification of the object lens on the linewidth is analyzed in detail. A qualitative analysis model is established, and the concepts of the threshold broadening and focus narrowing effects are proposed, with their influences and cooperative relation discussed. Besides, a linear structure with micrometer accuracy is manufactured at the millimeter scale.

유전자 알고리즘을 활용한 BIM 도면 주석 간섭 조정 기술 개발 (Development of BIM Drawing Annotation Interference Adjustment Technology Using Genetic Algorithm)

  • 전진규;박재호;김이제;진상윤
    • 한국BIM학회 논문집
    • /
    • 제13권4호
    • /
    • pp.85-95
    • /
    • 2023
  • In the process of creating drawings based on Building Information Modeling (BIM), automatically generated annotations can cause interference issues depending on the drawing type. This study aims to develop an algorithm for repositioning annotations using genetic algorithms to minimize such interferences. To achieve this, the Application Programming Interface (API) of BIM software was used to analyze data extractable from BIM drawing files. The process involved defining drawing data related to annotation repositioning, preprocessing this data, and deriving optimal placement coordinates for the annotations. Furthermore, applying the developed algorithm to the preliminary design drawings of small and medium-sized neighborhood facilities resulted in approximately a 95.37% decrease in annotation interference, indicating that the proposed algorithm can significantly enhance productivity in BIM-based drawing tasks.