• Title/Summary/Keyword: 명암도 변화

Search Result 192, Processing Time 0.027 seconds

A High Performance License Plate Recognition System (고속처리 자동차 번호판 인식시스템)

  • 남기환;배철수
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.6 no.8
    • /
    • pp.1352-1357
    • /
    • 2002
  • This Paper describes algorithm to extract license plates in vehicle images. Conventional methods perform preprocessing on the entire vehicle image to produce the edge image and binarize it. Hough transform is applied to the binary image to find horizontal and vertical lines, and the license plate area is extracted using the characteristics of license plates. Problems with this approach are that real-time processing is not feasible due to long processing time and that the license plate area is not extracted when lighting is irregular such as at night or when the plate boundary does not show up in the image. This research uses the gray level transition characteristics of license plates to verify the digit area by examining the digit width and the level difference between the background area the digit area, and then extracts the plate area by testing the distance between the verified digits. This research solves the problem of failure in extracting the license plates due to degraded plate boundary as in the conventional methods and resolves the problem of the time requirement by processing the real time such that practical application is possible. This paper Presents a power automated license plate recognition system, which is able to read license numbers of cars, even under circumstances, which are far from ideal. In a real-life test, the percentage of rejected plates wan 13%, whereas 0.4% of the plates were misclassified. Suggestions for further improvements are given.

An Extraction Method of Number Plates for Various Vehicles Using Digital Signal Analysis Processing Techniques (디지털 신호 분석 기법을 이용한 다양한 번호판 추출 방법)

  • Yang, Sun-Ok;Jun, Young-Min;Jung, Ji-Sang;Ryu, Sang-Hwan
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.45 no.3
    • /
    • pp.12-19
    • /
    • 2008
  • Detection of a number plate consists of three stages; division of a number plate, extraction of each character from the plate, recognition of the characters. Among of these three states, division stage of a number plate is the most important part and also the most time-consuming state. This paper suggests an effective region extraction method of a number plate for various images obtained from unmanned inspection systems of illegal parking violation, especially when we have to consider the diverse surrounding environments of roads. Our approaching method detects each region by investigating the characteristics in changes of brightness and intensity between the background part and character part, and the characteristics on character parts such as the sizes, heights, widths, and distance in between two characters. The method also divides a number plate into different types of the plate. This research can solve the number plate region detection failure problems caused by plate edge damages not only for Korean domestic number plates but also for new European style number plates. The method also reduces the time consumption by processing the detection in real-time, therefore, it can be used as a practical solution.

Analysis on Optimal Threshold Value for Infrared Video Flame Detection (적외선 영상의 화염 검출을 위한 최적 문턱치 분석)

  • Jeong, Soo-Young;Kim, Won-Ho
    • Journal of Satellite, Information and Communications
    • /
    • v.8 no.4
    • /
    • pp.100-104
    • /
    • 2013
  • In this paper, we present an optimal threshold setting method for flame detection of infrared thermal image. Conventional infrared flame detection methods used fixed intensity threshold to segment candidate flame regions and further processing is performed to decide correct flame detection. So flame region segmentation step using the threshold is important processing for fire detection algorithm. The threshold should be change in input image depends on camera types and operation conditions. We have analyzed the conventional thresholds composed of fixed-intensity, average, standard deviation, maximum value. Finally, we extracted that the optimal threshold value is more than summation of average and standard deviation, and less than maximum value. it will be enhance flame detection rate than conventional fixed-threshold method.

A Study on Image Recognition using Enhanced ART1 Algorithm (개선된 ART1 알고리즘을 이용한 이미지 인식에 관한 연구)

  • 천두억;윤성호;김광백
    • Journal of the Korea Society of Computer and Information
    • /
    • v.3 no.3
    • /
    • pp.17-22
    • /
    • 1998
  • As time goes on, that becomes an issue still more for truth from error of a seal in electronic settlement , or in important document in the field of image recognition. But on the other hand image treatment method of a seal have has the weakness until now. It makes indistinct distinction of part that light and darkness is changed sharply as the edge of things. So it has difficult that edge detection is extracted. In this paper, I investigated the pixel in a specific area by using enhanced smothing method and searched a value of frquent occurrence. The value of pixel is substituted and edge detection is extracted. After then it could be classified rightly according as viligence test is dynamically changed. I applied conventional of Yager's generated intersection operator among fuzzy logic operator in ART1 learning Algorithm. Application of suggested ART1 learning algorithm, it results in improved image recognition rate than a case of using the conventional ART1 algorithm

  • PDF

Flexible Background-Texture Analysis for Coronary Artery Extraction Based on Digital Subtraction Angiography (유동적인 배경 텍스쳐 분석을 통한 DSA 기반의 관상동맥 검출)

  • Park Sung-Ho;Lee Joong-Jae;Lee Geun-Soo;Kim Gye-Young
    • The KIPS Transactions:PartB
    • /
    • v.12B no.5 s.101
    • /
    • pp.543-552
    • /
    • 2005
  • This paper proposes the extraction of coronary arteries based on DSA(Digital Subtraction Angiography) through a texture analysis of background in the angiography. DSA is a well established modality for the visualization of coronary arteries. DSA involves the subtraction of a mask image - an image of the heart before injection of contrast medium - from live image. However, this technique is sensitive to the movement of background and can result to a wrong detection by the variance of background gray-level intensity between two images. Therefore, this paper solves a structural problem resulted from a background movement bV selecting an image which has the least difference of movement through an analysis of the similarity of background texture and proposes a method to extract only the blood vessel efficiently through local gray-level correction of the selected image. Using the coronary angiogram of 5 patients clinical data, we proved that the proposed method has the lower false-detection rate, approximately $2\%$, and the higher accuracy than the existing methods.

Automated Inspection System for Brake Shoe of Rolling Stock (철도차량용 제륜자의 자동 검사 시스템)

  • Kim, Hyun-Cheol;Kim, Whoi-Yul
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.46 no.6
    • /
    • pp.1-15
    • /
    • 2009
  • In this paper, we have proposed an automated system that accurately measures the thickness and unbalanced wear of brake shoes, and the distance between brake shoes and wheels for travelling rolling stock. The images of brake shoes are captured automatically while rolling stock is passing by an inspection station. And in order to measure the thickness, etc. the locations of brake shoes are first determined because the locations are not the same in the captured image. Toward this goal, shadow regions between the brake shoes and wheels are utilized that are common in all captured images. The boundary of the shadow regions is modeled by an second order polynomial, and constrained curve fitting method is adopted to detect a curve (the initial curve) that passes through the regions. Then, three curves that correspond to the front, back of brake shoes and wheels, and a line that passes through the vertical surface of brake shoes are detected using the initial curve and intensity change information. Finally, the thickness, etc. are calculated using the detected curves and line, and experimental results showed that the brake shoe thickness was measured with an accuracy of 0.654mm.

Development of Digital Leaf Authoring Tool for Virtual Landscape Production (가상 조경 생성을위한 디지털 잎 저작도구 개발)

  • Kim, Jinmo
    • Journal of the Korea Computer Graphics Society
    • /
    • v.21 no.5
    • /
    • pp.1-10
    • /
    • 2015
  • This study proposes a method of developing authoring tool that can easily and intuitively generate diverse digital leaves that compose virtual landscape. The main system of the proposed authoring tool consists of deformation method for the contour of leaf blade based on image warping, procedural modeling of leaf vein and visualization method based on mathematical model that expresses the color and brightness of leaves. First, the proposed authoring tool receives leaf input image and searches for contour information on the leaf blades. It then designs leaf blade deformation method that can generate diverse shapes of leaf blades in an intuitive structure using feature-based image warping. Based on the computed leaf blade contour, the system implements the generalized procedural modeling method suitable for the authoring tool that generates natural vein patterns appropriate for the leaf blade shape. Finally, the system applies visualization function that can express color and brightness of leaves and their changes over time using a mathematical model based on convolution sums of divisor functions. This paper provides texture support function so that the digital leaves that were generated using the proposed authoring tool can be used in a variety of three-dimensional digital contents field.

An Improvement of Recognition Performance Based on Nonlinear Equalization and Statistical Correlation (비선형 평활화와 통계적 상관성에 기반을 둔 인식성능 개선)

  • Shin, Hyun-Soo;Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.22 no.5
    • /
    • pp.555-562
    • /
    • 2012
  • This paper presents a hybrid method for improving the recognition performance, which is based on the nonlinear histogram equalization, features extraction, and statistical correlation of images. The nonlinear histogram equalization based on a logistic function is applied to adaptively improve the quality by adjusting the brightness of the image according to its intensity level frequency. The statistical correlation that is measured by the normalized cross-correlation(NCC) coefficient, is applied to rapidly and accurately express the similarity between the images. The local features based on independent component analysis(ICA) that is used to calculate the NCC, is also applied to statistically measure the correct similarity in each images. The proposed method has been applied to the problem for recognizing the 30-face images of 40*50 pixels. The experimental results show that the proposed method has a superior recognition performances to the method without performing the preprocessing, or the methods of conventional and adaptively modified histogram equalization, respectively.

ART2 Based Fuzzy Binarization Method with Low Information Loss (정보손실이 적은 ART2 기반 퍼지 이진화 방법)

  • Kim, Kwang-Baek
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.18 no.6
    • /
    • pp.1269-1274
    • /
    • 2014
  • In computer vision research, binarization procedure is one of the most frequently used tools to discriminate target objects from background in grey level binary image. Fuzzy binarization is a reliable technique in environment with high uncertainty such as medical image analysis by setting the threshold as the average of minimum and maximum brightness with triangle type fuzzy membership function. However, this technique is also known as contrast sensitive method thus its discrimination power is not so great when the image has low contrast difference between objects and backgrounds and suffer from information loss as a result. Thus, in this paper, we propose a fuzzy binarization using ART2 algorithm to handle such low contrast image analysis. Proposed ART2 algorithm is applied to determine the medium point of membership function in the fuzzy binarization paradigm. The proposed methods shows low information loss rate in our experiment.

A study on the polarization transmission characteristics of liquid crystal display devices by means of Berreman's $4{\times}4$ matrix method (베레만의 $4{\times}4$행렬방식을 이용한 액정표시소자의 편광투과특성 분석)

  • Yang, Byeong-Kwan;Kim, Gyu-Seok;Rho, Bong-Gyu;Kim, Jin-Seung;Par, Hee-Gap;Park, Chan;Lee, Hyong-Jong;Kim, Jae-Ki
    • Korean Journal of Optics and Photonics
    • /
    • v.8 no.3
    • /
    • pp.223-229
    • /
    • 1997
  • A source code is developed on the basis of Berreman's 4$\times$4 matrix formalism for the analysis of polarization transmission characteristics of twisted nematic liquid crystal display. By using the program, the polarization transmission characteristics of liquid crystal cells and polarizers are analyzed. For a normally white twisted nematic liquid crystal cell, we obtained a family of iso-contrast contours which helps to understand the viewing angle characteristics of the liquid crystal display device by using the cell. The program also help us to understand the variation of the degree of polarization as well as the deviation of the state of polarization of the light transmitted through the polarizer commonly used in the LCD according to the change in incidence angle. This result suggests the contrast of the images appearing on the LCD can be limited by the characteristics of the polarizer in addition to the liquid crystal cell.

  • PDF