• Title/Summary/Keyword: Segment Algorithm

Search Result 590, Processing Time 0.028 seconds

Development of a Stress ECG Analysis Algorithm Using Wavelet Transform (웨이브렛 변환을 이용한 스트레스 심전도 분석 알고리즘의 개발)

  • 이경중;박광리
    • Journal of Biomedical Engineering Research
    • /
    • v.19 no.3
    • /
    • pp.269-278
    • /
    • 1998
  • This paper describes a development of efficient stress ECG signal analysis algorithm. The algorithm consists of wavelet adaptive filter(WAF), QRS detector and ST segment detector. The WAF consists of a wavelet transform and an adaptive filter. The wavelet transform decomposed the ECG signal into seven levels using wavelet function for each high frequency bank and low frequency bank. The adaptive filter used the signal of the seventh lowest frequency band among the wavelet transformed signals as primary input. For detection of QRS complex, we made summed signals that are composed of high frequency bands including frequency component of QRS complex and applied the adaptive threshold method changing the amplitude of threshold according to RR interval. For evaluation of the performance of the WAF, we used two baseline wandering elimination filters including a standard filter and a general adaptive filter. WAF showed a better performance than compared filters in the noise elimination characteristics and signal distortion. For evaluation of WAF showed a better performance than compared filters in the noise elimination characteristics and signal distortion. For evaluation of results of QRS complex detection, we compared our algorithm with existing algorithms using MIT/BIH database. Our algorithm using summed signals showed the accuracy of 99.67% and the higher performance of QRS detection than existing algorithms. Also, we used European ST-T database and patient data to evaluate measurement of the ST segment and could measure the ST segment adaptively according to change of heart rate.

  • PDF

Automatic partial shape recognition system using adaptive resonance theory (적응공명이론에 의한 자동 부분형상 인식시스템)

  • 박영태;양진성
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.3
    • /
    • pp.79-87
    • /
    • 1996
  • A new method for recognizing and locating partially occluded or overlapped two-dimensional objects regardless of their size, translation, and rotation, is presented. Dominant points approximating occuluding contoures of objects are generated by finding local maxima of smoothed k-cosine function, and then used to guide the contour segment matching procedure. Primitives between the dominant points are produced by projecting the local contours onto the line between the dominant points. Robust classification of primitives. Which is crucial for reliable partial shape matching, is performed using adaptive resonance theory (ART2). The matched primitives having similar scale factors and rotation angles are detected in the hough space to identify the presence of the given model in the object scene. Finally the translation vector is estimated by minimizing the mean squred error of the matched contur segment pairs. This model-based matching algorithm may be used in diveerse factory automation applications since models can be added or changed simply by training ART2 adaptively without modifying the matching algorithm.

  • PDF

An Adaptive and Robust Inspection Algorithm of PCB Patterns Based on Movable Segments (동적 세그먼트 기반 PCB 패턴의 적응 검사 알고리즘)

  • Moon Soon-Hwan;Kim Gyung-Bum
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.23 no.3 s.180
    • /
    • pp.102-109
    • /
    • 2006
  • Several methods for PCB pattern inspection have been tried to detect fine detects in pad contours, but their low detection accuracy results from pattern variations originating from etching, printing and handling processes. The adaptive inspection algorithm has been newly proposed to extract minute defects based on movable segments. With gerber master images of PCB, vertex extractions of a pad boundary are made and then a lot of segments are constructed in master data. The pad boundary is composed of segment units. The proposed method moves these segments to optimal directions of a pad boundary and so adaptively matches segments to pad contours of inspected images, irrespectively of various pattern variations. It makes a fast, accurate and reliable inspection of PCB patterns. Its performances are also evaluated with several images.

Study on Robust Driving for Autonomous Vehicle in Real-Time (자율주행차량의 실시간 강건한 주행을 위한 연구)

  • 이대은;김정훈;김영배
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2004.10a
    • /
    • pp.908-911
    • /
    • 2004
  • In this paper, we describe a robust image processing algorithm to recognize the road lane in real-time. For the real-time processing, a detection area is decided by a lane segment of a previous frame and edges are detected on the basis of the lane width. For the robust driving, the global threshold with the Otsu algorithm is used to get a binary image in a frame. Therefore, reliable edges are obtained from the algorithms suggested in this paper in a short time. Lastly, the lane segment is found by hough transform. We made a RC(Radio Control) car equipped with a vision system and verified these algorithms using the RC Car.

  • PDF

Study on Effective Lane Detection Using Hough Transform and Lane Model (허프변환과 차선모델을 이용한 효과적인 차선검출에 관한 연구)

  • Kim, Gi-Seok;Lee, Jin-Wook;Cho, Jae-Soo
    • Proceedings of the IEEK Conference
    • /
    • 2009.05a
    • /
    • pp.34-36
    • /
    • 2009
  • This paper proposes an effective lane detection algorithm using hugh transform and lane model. The proposed lane detection algorithm includes two major components, i.e., lane marks segmentation and an exact lane extraction using a novel postprocessing technique. The first step is to segment lane marks from background images using HSV color model. Then, a novel postprocessing is used to detect an exact lane using Hugh transform and lane models(linear and curved lane models). The postprocessing consists of three parts, i.e, thinning process, Hugh Transform and filtering process. We divide input image into three regions of interests(ROIs). Based on lane curve function(LCF), we can detect an exact lane from various extracted lane lines. The lane models(linear and curved lane mode]) are used in order to judge whether each lane segment is fit or not in each ROIs. Experimental results show that the proposed scheme is very effective in lane detection.

  • PDF

Noise Removal for Level Set based Flower Segmentation (레벨셋 기반 꽃 분할을 위한 노이즈 제거)

  • Park, Sang Cheol;Oh, Kang Han;Na, In Seop;Kim, Soo Hyung;Yang, Hyung Jeong;Lee, Guee Sang
    • Smart Media Journal
    • /
    • v.1 no.2
    • /
    • pp.34-39
    • /
    • 2012
  • In this paper, post-processing step is presented to remove noises and develop a fully automated scheme to segment flowers in natural scene images. The scheme to segment flowers using a level set algorithm in the natural scene images produced unexpected and isolated noises because the level set relies only on the color and edge information. The experimental results shows that the proposed method successfully removes noises in the foreground and background.

  • PDF

Development of a Multi-template type Image Segmentation Algorithm for the Recognition of Semiconductor Wafer ID (반도체 웨이퍼 ID 인식을 위한 다중템플릿형 영상분할 알고리즘 개발)

  • Ahn, In-Mo
    • The Transactions of the Korean Institute of Electrical Engineers P
    • /
    • v.55 no.4
    • /
    • pp.167-175
    • /
    • 2006
  • This paper presents a method to segment semiconductor wafer ID on poor quality images. The method is based on multiple templates and normalized gray-level correlation (NGC) method. If the lighting condition is not so good and hence, we can not control the image quality, target image to be inspected presents poor quality ID and it is not easy to identify and then recognize the ID characters. Conventional several method to segment the interesting ID regions fails on the bad quality images. In this paper, we propose a multiple template method, which uses combinational relation of multiple templates from model templates to match several characters of the inspection images. To find out the optimal solution of multiple template model in ID regions, we introduce newly-developed snake algorithm. Experimental results using images from real FA environment are presented.

Linear Ordering with Incremental Merging for Circuit Netlist Partitioning (회로 결선도 분할을 위해 점진적 병합을 이용한 선형배열)

  • 성광수
    • Journal of the Korean Institute of Telematics and Electronics C
    • /
    • v.35C no.9
    • /
    • pp.21-28
    • /
    • 1998
  • In this paper, we propose an efficient linear ordering algorithm, called LIME, for netlist partitioning. LIME incrementally merges two segments which are selected based on the proposed cost function until only one segment remains. The final resultant segment then corresponds to the linear ordering. LIME also runs extremely fast, because it exploits sparsity of netlist. Compared to the earlier work, the proposed algorithm is eight times faster in producing linear ordering and yields an average of 17% improvement for the multi-way scaled cost partitioning.

  • PDF

Segment matching using matching measure distribution over disparities (변이별 정합 척도 분포를 이용한 선소의 정합)

  • 강창순;남기곤
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.34S no.3
    • /
    • pp.74-83
    • /
    • 1997
  • In this paper, a new stereo matching algorithm is proposed which uses th econstrainted optimization technique and the matching measures between the segments extracted from zero-crossing edges. The initial matching measures and average disparities are calculated by the features of segments on the searching window of the left and right images. The matching measure is calculated by applying an exponential function using the differences of slope, overlapped length and intensity. The coherency constraint is that neighbouring image points corresponding to the same object should have nearly the same disparities. The matching measures are iteratively updated by applying the coherency constraint. Simulation results on various images show that the proposed algorithm more acculately extracts the segment disparity.

  • PDF

Detection of Road Features Using MAP Estimation Algorithm In Radar Images (MAP 추정 알고리즘에 의한 레이더 영상에서 도로검출)

  • 김순백;이수흠;김두영
    • Proceedings of the Korea Institute of Convergence Signal Processing
    • /
    • 2003.06a
    • /
    • pp.62-65
    • /
    • 2003
  • We propose an algorithm for almost unsupervised detection of linear structures, in particular, axes in road network and river, as seen in synthetics aperture radar (SAR) images. The first is local step and used to extract linear features from the speckle radar image, which are treated as road segment candidates. We present two local line detectors as well as a method for fusing information from these detectors. The second is global step, we identify the real roads among the segment candidates by defining a Markov random field (MRF) on a set of segments, which introduces contextual knowledge about the shape of road objects.

  • PDF