• Title/Summary/Keyword: Contour Extraction

Search Result 255, Processing Time 0.023 seconds

A 2D FLIR Image-based 3D Target Recognition using Degree of Reliability of Contour (윤곽선의 신뢰도를 고려한 2차원 적외선 영상 기반의 3차원 목표물 인식 기법)

  • 이훈철;이청우;배성준;이광연;김성대
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.12B
    • /
    • pp.2359-2368
    • /
    • 1999
  • In this paper we propose a 2D FLIR image-based 3D target recognition system which performs group-to-ground vehicle recognition using the target contour and its degree of reliability extracted from FLIR image. First we extract target from background in FLIR image. Then we define contour points of the extracted target which have high edge gradient magnitude and brightness value as reliable contour point and make reliable contour by grouping all reliable contour points. After that we extract corresponding reliable contours from model contour image and perform comparison between scene and model features which are calculated by DST(discrete sine transform) of reliable contours. Experiment shows that the proposed algorithm work well and even in case of imperfect target extraction it showed better performance then conventional 2D contour-based matching algorithms.

  • PDF

Moving Object Tracking Using Active Contour Model (동적 윤곽 모델을 이용한 이동 물체 추적)

  • Han, Kyu-Bum;Baek, Yoon-Su
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.27 no.5
    • /
    • pp.697-704
    • /
    • 2003
  • In this paper, the visual tracking system for arbitrary shaped moving object is proposed. The established tracking system can be divided into model based method that needs previous model for target object and image based method that uses image feature. In the model based method, the reliable tracking is possible, but simplification of the shape is necessary and the application is restricted to definite target mod el. On the other hand, in the image based method, the process speed can be increased, but the shape information is lost and the tracking system is sensitive to image noise. The proposed tracking system is composed of the extraction process that recognizes the existence of moving object and tracking process that extracts dynamic characteristics and shape information of the target objects. Specially, active contour model is used to effectively track the object that is undergoing shape change. In initializatio n process of the contour model, the semi-automatic operation can be avoided and the convergence speed of the contour can be increased by the proposed effective initialization method. Also, for the efficient solution of the correspondence problem in multiple objects tracking, the variation function that uses the variation of position structure in image frame and snake energy level is proposed. In order to verify the validity and effectiveness of the proposed tracking system, real time tracking experiment for multiple moving objects is implemented.

Robust Extraction of Lean Tissue Contour From Beef Cut Surface Image

  • Heon Hwang;Lee, Y.K.;Y.r. Chen
    • Proceedings of the Korean Society for Agricultural Machinery Conference
    • /
    • 1996.06c
    • /
    • pp.780-791
    • /
    • 1996
  • A hybrid image processing system which automatically distinguished lean tissues in the image of a complex beef cut surface and generated the lean tissue contour has been developed. Because of the in homegeneous distribution and fuzzy pattern of fat and lean tissue on the beef cut, conventional image segmentation and contour generation algorithm suffer from a heavy computing requirement, algorithm complexity and poor robustness. The proposed system utilizes an artificial neural network enhance the robustness of processing. The system is composed of pre-network , network and post-network processing stages. At the pre-network stage, gray level images of beef cuts were segmented and resized to be adequate to the network input. Features such as fat and bone were enhanced and the enhanced input image was converted tot he grid pattern image, whose grid was formed as 4 X4 pixel size. at the network stage, the normalized gray value of each grid image was taken as the network input. Th pre-trained network generated the grid image output of the isolated lean tissue. A training scheme of the network and the separating performance were presented and analyzed. The developed hybrid system showed the feasibility of the human like robust object segmentation and contour generation for the complex , fuzzy and irregular image.

  • PDF

The Contour Extraction of Lung Parenchyma on the EBT Image Acquired with Spirometric Gating (호흡 연동에 의한 EBT 단면 영상에서의 폐실질 윤곽선 검출)

  • Kim, Myoung-Nam;Won, Chul-Ho
    • Journal of Sensor Science and Technology
    • /
    • v.8 no.2
    • /
    • pp.154-162
    • /
    • 1999
  • In this paper, we acquired EBT section images of lung parenchyma using fabricated spirometric gating device and proposed new energy function based on dynamic contour model in order to extracted the contour of the lung parenchyma in EBT images. In EBT images, gray level of the lungs is lower than other region. we extracted the lungs contour using the new energy function considering gray level and contour vector of the lung parenchyma region from EBT images. As we compared the proposed method with the conventional method, we confirmed that detection method using proposed energy function was valid.

  • PDF

Adaptive Segment-length Thresholding for Map Contour Extraction (등고선 추출을 위한 적응적 길이 임계화)

  • 박천주;오명관;전병민
    • The Journal of the Korea Contents Association
    • /
    • v.3 no.4
    • /
    • pp.23-28
    • /
    • 2003
  • This paper describes, in order to extract contour from topographic map image, an adaptive segment-length thresholding using a threshold depended on target image. First of all, after recognizing the primary symbols and detecting two edges from the projection histogram of the elevation value area, the threshold value is determined by the distance between the edges. Then, the subdivision is peformed by searching a branch point and erasing its neighboring Hack pixels. And contour components are extracted by segment-length thresholding. The experimental result shows that the final image contains non-contour component of 2.41% and contour one of 97.59%.

  • PDF

Extraction of Blood Flow of Brachial Artery on Color Doppler Ultrasonography by Using 4-Directional Contour Tracking and K-Means Algorithm (4 방향 윤곽선 추적과 K-Means 알고리즘을 이용한 색조 도플러 초음파 영상에서 상환 동맥의 혈류 영역 추출)

  • Park, Joonsung;Kim, Kwang Baek
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.11
    • /
    • pp.1411-1416
    • /
    • 2020
  • In this paper, we propose a method of extraction analysis of blood flow area on color doppler ultrasonography by using 4-directional contour tracking and K-Means algorithm. In the proposed method, ROI is extracted and a binarization method with maximum contrast as a threshold is applied to the extracted ROI. 4-directional contour algorithm is applied to extract the trapezoid shaped region which has blood flow area of brachial artery from the binarized ROI. K-Means based quantization is then applied to accurately extract the blood flow area of brachial artery from the trapezoid shaped region. In experiment, the proposed method successfully extracts the target area in 28 out of 30 cases (93.3%) with field expert's verification. And comparison analysis of proposed K-Means based blood flow area extraction on 30 color doppler ultrasonography and brachial artery blood flow ultrasonography provided by a specialist yielded a result of 94.27% accuracy on average.

Design and Implementation of Eye-Gaze Estimation Algorithm based on Extraction of Eye Contour and Pupil Region (눈 윤곽선과 눈동자 영역 추출 기반 시선 추정 알고리즘의 설계 및 구현)

  • Yum, Hyosub;Hong, Min;Choi, Yoo-Joo
    • The Journal of Korean Association of Computer Education
    • /
    • v.17 no.2
    • /
    • pp.107-113
    • /
    • 2014
  • In this study, we design and implement an eye-gaze estimation system based on the extraction of eye contour and pupil region. In order to effectively extract the contour of the eye and region of pupil, the face candidate regions were extracted first. For the detection of face, YCbCr value range for normal Asian face color was defined by the pre-study of the Asian face images. The biggest skin color region was defined as a face candidate region and the eye regions were extracted by applying the contour and color feature analysis method to the upper 50% region of the face candidate region. The detected eye region was divided into three segments and the pupil pixels in each pupil segment were counted. The eye-gaze was determined into one of three directions, that is, left, center, and right, by the number of pupil pixels in three segments. In the experiments using 5,616 images of 20 test subjects, the eye-gaze was estimated with about 91 percent accuracy.

  • PDF

The Identifier Recognition from Shipping Container Image by Using Contour Tracking and Self-Generation Supervised Learning Algorithm Based on Enhanced ART1 (윤곽선 추적과 개선된 ART1 기반 자가 생성 지도 학습 알고리즘을 이용한 운송 컨테이너 영상의 식별자 인식)

  • 김광백
    • Journal of Intelligence and Information Systems
    • /
    • v.9 no.3
    • /
    • pp.65-79
    • /
    • 2003
  • In general, the extraction and recognition of identifier is very hard work, because the scale or location of identifier is not fixed-form. And, because the provided image is contained by camera, it has some noises. In this paper, we propose methods for automatic detecting edge using canny edge mask. After detecting edges, we extract regions of identifier by detected edge information's. In regions of identifier, we extract each identifier using contour tracking algorithm. The self-generation supervised learning algorithm is proposed for recognizing them, which has the algorithm of combining the enhanced ART1 and the supervised teaming method. The proposed method has applied to the container images. The extraction rate of identifier obtained by using contour tracking algorithm showed better results than that from the histogram method. Furthermore, the recognition rate of the self-generation supervised teaming method based on enhanced ART1 was improved much more than that of the self-generation supervised learning method based conventional ART1.

  • PDF

Evaluation of Cardiac Function Analysis System Using Magnetic Resonance Images

  • Tae, Ki-Sik;Suh, Tae-Suk;Choe, Bo-Young;Lee, Hyoung-Koo;Shinn, Kyung-Sub;Jung, Seung-Eun;Lee, Jae-Moon
    • Progress in Medical Physics
    • /
    • v.10 no.3
    • /
    • pp.159-168
    • /
    • 1999
  • Cardiac disease is one of the leading causes of death in Korea. In quantitative analysis of cardiac function and morphological information by three-dimensional reconstruction of magnetic resonance images, left ventricle provides an important role functionally and physiologically. However, existing procedures mostly rely on the extensive human interaction and are seldom evaluated on clinical applications. In this study, we developed a system which could perform automatic extraction of enpicardial and endocardial contour and analysis of cardiac function to evaluate reliability and stability of each system comparing with the result of ARGUS system offered 1.5T Siemens MRI system and manual method performed by clinicians. For various aspects, we investigated reliability of each system by compared with left ventricular contour, end-diastolic volume (EDV), end-systolic volume (ESV), stock volume (SV), ejection fraction (EF), cardiac output (CO) and wall thickness (WT). When comparing with manual method, extracted results of developed process using minimum error threshold (MET) method that automatically extracts contour from cardiac MR images and ARGUS system were demonstrated as successful rate 90% of the contour extraction. When calculating cardiac function parameters using MET and comparing with using correlation coefficients analysis method, the process extracts endocardial and epicardial contour using MET, values from automatic and ARGUS method agreed with manual values within :t 3% average error. It was successfully demonstrated that automatic method using threshold technique could provide high potential for assessing of each parameters with relatively high reliability compared with manual method. In this study, the method developed in this study could reduce processing time compared with ARGUS and manual method due to a simple threshold technique. This method is useful for diagnosis of cardiac disease, simulating physiological function and amount of blood flow of left ventricle. In addition, this method could be valuable in developing automatic systems in order to apply to other deformable image models.

  • PDF