• 제목/요약/키워드: Orientation Features

검색결과 305건 처리시간 0.025초

Registration of Three-Dimensional Point Clouds Based on Quaternions Using Linear Features (선형을 이용한 쿼터니언 기반의 3차원 점군 데이터 등록)

  • Kim, Eui Myoung;Seo, Hong Deok
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • 제38권3호
    • /
    • pp.175-185
    • /
    • 2020
  • Three-dimensional registration is a process of matching data with or without a coordinate system to a reference coordinate system, which is used in various fields such as the absolute orientation of photogrammetry and data combining for producing precise road maps. Three-dimensional registration is divided into a method using points and a method using linear features. In the case of using points, it is difficult to find the same conjugate point when having different spatial resolutions. On the other hand, the use of linear feature has the advantage that the three-dimensional registration is possible by using not only the case where the spatial resolution is different but also the conjugate linear feature that is not the same starting point and ending point in point cloud type data. In this study, we proposed a method to determine the scale and the three-dimensional translation after determining the three-dimensional rotation angle between two data using quaternion to perform three-dimensional registration using linear features. For the verification of the proposed method, three-dimensional registration was performed using the linear features constructed an indoor and the linear features acquired through the terrestrial mobile mapping system in an outdoor environment. The experimental results showed that the mean square root error was 0.001054m and 0.000936m, respectively, when the scale was fixed and if not fixed, using indoor data. The results of the three-dimensional transformation in the 500m section using outdoor data showed that the mean square root error was 0.09412m when the six linear features were used, and the accuracy for producing precision maps was satisfied. In addition, in the experiment where the number of linear features was changed, it was found that nine linear features were sufficient for high-precision 3D transformation through almost no change in the root mean square error even when nine linear features or more linear features were used.

Camera Calibration for Machine Vision Based Autonomous Vehicles (머신비젼 기반의 자율주행 차량을 위한 카메라 교정)

  • Lee, Mun-Gyu;An, Taek-Jin
    • Journal of Institute of Control, Robotics and Systems
    • /
    • 제8권9호
    • /
    • pp.803-811
    • /
    • 2002
  • Machine vision systems are usually used to identify traffic lanes and then determine the steering angle of an autonomous vehicle in real time. The steering angle is calculated using a geometric model of various parameters including the orientation, position, and hardware specification of a camera in the machine vision system. To find the accurate values of the parameters, camera calibration is required. This paper presents a new camera-calibration algorithm using known traffic lane features, line thickness and lane width. The camera parameters considered are divided into two groups: Group I (the camera orientation, the uncertainty image scale factor, and the focal length) and Group II(the camera position). First, six control points are extracted from an image of two traffic lines and then eight nonlinear equations are generated based on the points. The least square method is used to find the estimates for the Group I parameters. Finally, values of the Group II parameters are determined using point correspondences between the image and its corresponding real world. Experimental results prove the feasibility of the proposed algorithm.

A Study on Game Character Classification Based on Texture and Edge Orientation Feature (질감 및 에지 방향 특징에 기반한 게임 캐릭터 분류에 관한 연구)

  • Park, Chang-Min
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • 제16권6호
    • /
    • pp.1318-1324
    • /
    • 2012
  • This paper proposes a novel method for Game character classification based on texture and edge orientation feature. The character dose not move(NPC) and move the character is classified. Classification of property within the character of straight line segments are used to extract features. First, the character inside edge feature extraction and then calculates EEDH, SSPD. The extracted attribute represents the energy of a particular direction. Thus, these properties were used to classify of NPC and Monster. The proposed method, the user can reduce the unnecessary time in the game.

A Robust Fingertip Extraction and Extended CAMSHIFT based Hand Gesture Recognition for Natural Human-like Human-Robot Interaction (강인한 손가락 끝 추출과 확장된 CAMSHIFT 알고리즘을 이용한 자연스러운 Human-Robot Interaction을 위한 손동작 인식)

  • Lee, Lae-Kyoung;An, Su-Yong;Oh, Se-Young
    • Journal of Institute of Control, Robotics and Systems
    • /
    • 제18권4호
    • /
    • pp.328-336
    • /
    • 2012
  • In this paper, we propose a robust fingertip extraction and extended Continuously Adaptive Mean Shift (CAMSHIFT) based robust hand gesture recognition for natural human-like HRI (Human-Robot Interaction). Firstly, for efficient and rapid hand detection, the hand candidate regions are segmented by the combination with robust $YC_bC_r$ skin color model and haar-like features based adaboost. Using the extracted hand candidate regions, we estimate the palm region and fingertip position from distance transformation based voting and geometrical feature of hands. From the hand orientation and palm center position, we find the optimal fingertip position and its orientation. Then using extended CAMSHIFT, we reliably track the 2D hand gesture trajectory with extracted fingertip. Finally, we applied the conditional density propagation (CONDENSATION) to recognize the pre-defined temporal motion trajectories. Experimental results show that the proposed algorithm not only rapidly extracts the hand region with accurately extracted fingertip and its angle but also robustly tracks the hand under different illumination, size and rotation conditions. Using these results, we successfully recognize the multiple hand gestures.

A Parallel-Architecture Processor Design for the Fast Multiplication of Homogeneous Transformation Matrices (Homogeneous Transformation Matrix의 곱셈을 위한 병렬구조 프로세서의 설계)

  • Kwon Do-All;Chung Tae-Sang
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • 제54권12호
    • /
    • pp.723-731
    • /
    • 2005
  • The $4{\times}4$ homogeneous transformation matrix is a compact representation of orientation and position of an object in robotics and computer graphics. A coordinate transformation is accomplished through the successive multiplications of homogeneous matrices, each of which represents the orientation and position of each corresponding link. Thus, for real time control applications in robotics or animation in computer graphics, the fast multiplication of homogeneous matrices is quite demanding. In this paper, a parallel-architecture vector processor is designed for this purpose. The processor has several key features. For the accuracy of computation for real application, the operands of the processors are floating point numbers based on the IEEE Standard 754. For the parallelism and reduction of hardware redundancy, the processor takes column vectors of homogeneous matrices as multiplication unit. To further improve the throughput, the processor structure and its control is based on a pipe-lined structure. Since the designed processor can be used as a special purpose coprocessor in robotics and computer graphics, additionally to special matrix/matrix or matrix/vector multiplication, several other useful instructions for various transformation algorithms are included for wide application of the new design. The suggested instruction set will serve as standard in future processor design for Robotics and Computer Graphics. The design is verified using FPGA implementation. Also a comparative performance improvement of the proposed design is studied compared to a uni-processor approach for possibilities of its real time application.

Corridor Navigation of the Mobile Robot Using Image Based Control

  • Han, Kyu-Bum;Kim, Hae-Young;Baek, Yoon-Su
    • Journal of Mechanical Science and Technology
    • /
    • 제15권8호
    • /
    • pp.1097-1107
    • /
    • 2001
  • In this paper, the wall following navigation algorithm of the mobile robot using a mono vision system is described. The key points of the mobile robot navigation system are effective acquisition of the environmental information and fast recognition of the robot position. Also, from this information, the mobile robot should be appropriately controlled to follow a desired path. For the recognition of the relative position and orientation of the robot to the wall, the features of the corridor structure are extracted using the mono vision system, then the relative position, the offset distance and steering angle of the robot from the wall, is derived for a simple corridor geometry. For the alleviation of the computation burden of the image processing, the Kalman filter is used to reduce search region in the image space for line detection. Next, the robot is controlled by this information to follow the desired path. The wall following control scheme by the PD control scheme is composed of two control parts, the approaching control and the orientation control, and each control is performed by steering and forward-driving motion of the robot. To verify the effectiveness of the proposed algorithm, the real time navigation experiments are performed. Through the result of the experiments, the effectiveness and flexibility of the suggested algorithm are verified in comparison with a pure encoder-guided mobile robot navigation system.

  • PDF

Crowd Activity Recognition using Optical Flow Orientation Distribution

  • Kim, Jinpyung;Jang, Gyujin;Kim, Gyujin;Kim, Moon-Hyun
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제9권8호
    • /
    • pp.2948-2963
    • /
    • 2015
  • In the field of computer vision, visual surveillance systems have recently become an important research topic. Growth in this area is being driven by both the increase in the availability of inexpensive computing devices and image sensors as well as the general inefficiency of manual surveillance and monitoring. In particular, the ultimate goal for many visual surveillance systems is to provide automatic activity recognition for events at a given site. A higher level of understanding of these activities requires certain lower-level computer vision tasks to be performed. So in this paper, we propose an intelligent activity recognition model that uses a structure learning method and a classification method. The structure learning method is provided as a K2-learning algorithm that generates Bayesian networks of causal relationships between sensors for a given activity. The statistical characteristics of the sensor values and the topological characteristics of the generated graphs are learned for each activity, and then a neural network is designed to classify the current activity according to the features extracted from the multiple sensor values that have been collected. Finally, the proposed method is implemented and tested by using PETS2013 benchmark data.

A Semantic Orientation Prediction Method of Sentiment Features Based on the General and Domain-Dependent Characteristics (일반적, 영역 의존적 특성을 반영한 감정 자질의 의미지향성 추정 방법)

  • Hwang, Jaewon;Ko, Youngjoong
    • Annual Conference on Human and Language Technology
    • /
    • 한국정보과학회언어공학연구회 2009년도 제21회 한글 및 한국어 정보처리 학술대회
    • /
    • pp.155-159
    • /
    • 2009
  • 본 논문은 한국어 문서 감정분류를 위한 중요한 어휘 자원인 감정자질(Sentiment Feature)의 의미지향성(Semantic Orientation) 추정을 위해 일반적인 특성과 영역(Domain) 의존적인 특성을 반영하여 한국어 문서 감정분류(Sentiment Classification)의 성능 향상을 얻을 수 있는 기법을 제안한다. 감정자질의 의미지 향성은 검색 엔진을 통해 추출한 각 감정 자질의 스니핏(Snippet)과 실험 말뭉치를 이용하여 추정할 수 있다. 검색 엔진을 통해 추출된 스니핏은 감정자질의 일반적인 특성을 반영하며, 실험 말뭉치는 분류하고자 하는 영역 의존적인 특성을 반영한다. 이렇게 얻어진 감정자질의 의미지향성 수치는 각 문장의 감정강도를 추정하기 위해 이용되며, 문장의 감정 강도의 값을 TF-IDF 가중치 기법에 접목하여 감정자질의 가중치를 책정한다. 최종적으로 학습 과정에서 긍정 문서에서는 긍정 감정자질, 부정 문서에서는 부정 감정자질을 대상으로 추가 가중치를 부여하여 학습하였다. 본 논문에서는 문서 분류에 뛰어난 성능을 보여주는 지지 벡터 기계(Support Vector Machine)를 사용하여 제안한 방법의 성능을 평가한다. 평가 결과, 일반적인 정보 검색에서 사용하는 내용어(Content Word) 기반의 자질을 사용한 경우보다 3.1%의 성능향상을 보였다.

  • PDF

Application of Ground Penetrating Radar for Archaeological Monuments (지하레이다를 이용한 고고학 탐사)

  • Shon, Howoong
    • Economic and Environmental Geology
    • /
    • 제29권6호
    • /
    • pp.745-752
    • /
    • 1996
  • A ground penetrating radar survey with a 500 MHz radar antenna was applied to make archaeological investigation in Nakajima of Ishikawa Prefecture, Japan. The ability of the radar system to aid in the archaeological preservation of burial ground was the primary concern of the experiments. The average variance of the radar wave returned from progressively deeper reflectors in a tomb were contoured at 2.4 nanoseconds intervals. The results of analysis indicates the location of trenches and the coffin area at the tomb site. The orientation of the coffin is dearly defined on contour maps made below 9.6 nanoseconds horizon. The general features detected by the GPR were also reconfirmed by electric resistivity survey made at the site. The radar was accurate in ascertaining the location, orientation, and the general construction style of the coffin.

  • PDF

Characterization of the Spatial Variability of Paper Formation Using a Continuous Wavelet Transform

  • Keller, D.Steven;Luner, Philip;Pawlak, Joel J.
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • 제32권5호
    • /
    • pp.14-25
    • /
    • 2000
  • In this investigation, a wavelet transform analysis was used to decompose beta-radiographic formation images into spectral and spatial components. Conventional formation analysis may use spectral analysis, based on Fourier transformation or variance vs. zone size, to describe the grammage distribution of features such as flocs, streaks and mean fiber orientation. However, these methods have limited utility for the analysis of statistically stationary data sets where variance is not uniform with position, e.g. paper machine CD profiles (especially those that contain streaks). A continuous wavelet transform was used to analyze formation data arrays obtained from radiographic imaging of handsheets and cross machine paper samples. The response of the analytical method to grammage, floc size distribution, mean fiber orientation an sensitivity to feature localization were assessed. From wavelet analysis, the change in scale of grammage variation as a function of position was used to demonstrate regular and isolated differences in the formed structure.

  • PDF