• 제목/요약/키워드: Image Thinning

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Invariant Image Matching using Linear Features (선형특징을 사용한 불변 영상정합 기법)

  • Park, Se-Je;Park, Young-Tae
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.12
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    • pp.55-62
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    • 1998
  • Matching two images is an essential step for many computer vision applications. A new approach to the scale and rotation invariant scene matching, using linear features, is presented. Scene or model images are described by a set of linear features approximating edge information, which can be obtained by the conventional edge detection, thinning, and piecewise linear approximation. A set of candidate parameters are hypothesized by mapping the angular difference and a new distance measure to the Hough space and by detecting maximally consistent points. These hypotheses are verified by a fast linear feature matching algorithm composed of a single-step relaxation and a Hough technique. The proposed method is shown to be much faster than the conventional one where the relaxation process is repeated until convergence, while providing matching performance robust to the random alteration of the linear features, without a priori information on the geometrical transformation parameters.

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A Study on Equation Recognition Using Tree Structure (트리 구조를 이용한 수식 인식 연구)

  • Park, Byung-Joon;Kim, Hyun-Sik;Kim, Wan-Tae
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.4
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    • pp.340-345
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    • 2018
  • The Compared to general sentences, the Equation uses a complex structure and various characters and symbols, so that it is not possible to input all the character sets by simply inputting a keyboard. Therefore, the editor is implemented in a text editor such as Hangul or Word. In order to express the Equation properly, it is necessary to have the learner information which can be meaningful to interpret the syntax. Even if a character is input, it can be represented by another expression depending on the relationship between the size and the position. In other words, the form of the expression is expressed as a tree model considering the relationship between characters and symbols such as the position and size to be expressed. As a field of character recognition application, a technique of recognizing characters or symbols(code) has been widely known, but a method of inputting and interpreting a Equation requires a more complicated analysis process than a general text. In this paper, we have implemented a Equation recognizer that recognizes characters in expressions and quickly analyzes the position and size of expressions.

Vehicle Information Recognition and Electronic Toll Collection System with Detection of Vehicle feature Information in the Rear-Side of Vehicle (차량후면부 차량특징정보 검출을 통한 차량정보인식 및 자동과금시스템)

  • 이응주
    • Journal of Korea Multimedia Society
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    • v.7 no.1
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    • pp.35-43
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    • 2004
  • In this paper, we proposed a vehicle recognition and electronic toll collection system with detection and classification of vehicle identification mark and emblem as well as recognition of vehicle license plate to unman toll fee collection system or incoming/outcoming vehicles to an institution. In the proposed algorithm, we first process pre-processing step such as noise reduction and thinning from the rear side input image of vehicle and detect vehicle mark, emblem and license plate region using intensity variation informations, template masking and labeling operation. And then, we classify the detected vehicle features regions into vehicle mark and emblem as well as recognize characters and numbers of vehicle license plate using hybrid and seven segment pattern vector. To show the efficiency of the proposed algorithm, we tested it on real vehicle images of implemented vehicle recognition system in highway toll gate and found that the proposed method shows good feature detection/classification performance regardless of irregular environment conditions as well as noise, size, and location of vehicles. And also, the proposed algorithm may be utilized for catching criminal vehicles, unmanned toll collection system, and unmanned checking incoming/outcoming vehicles to an institution.

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A Recognition of Handwritten English Characters Using Back Propagation Algorithm and Dictionary (역전파 알고리듬과 사전을 이용한 필기체 영문자 인식)

  • 김응성;조성환;이근영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.2
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    • pp.157-168
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    • 1993
  • In this paper, it is shown that neural networks trained with back propagation algorithm and dictionary can be applied to recognize handwritten English characters. To eliminate the useless data part and to minimize the variety of characters from the scanned image file, various preprocessings : that is, segmentation, centering, noise filtering, sealing and thinning are performed. After these, characteristic features are derived from thinned character pattern. The neural network is trained by using the extracted features for sample data, and all test data are classified into English alphabets according to their features through the neural network. Finally, the ways of reducing learning time and improving recognition rate, and the relationship between learning time and hidden layer nodes are considered. As a result of this study, after successful training, a high recognition rate has been obtained with this system for the trained patterns and about 93% for test patterns. Using dictionary, the recognition rate was about 97% for test pattern.

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Visual Preference Evaluation on Forest Working Systems' Characteristics for Forest Scenic Beauty Management (산림풍치자원관리(山林風致資源管理)를 위한 산림시업특성별(山林施業特性別) 시각선호도(視覺選好度) 평가(評價))

  • Song, Hyung Sop
    • Journal of Korean Society of Forest Science
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    • v.88 no.3
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    • pp.309-319
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    • 1999
  • This study was conducted to get forest scenic beauty management information toward forest working systems; characteristics in Larix forest stands. 35 different alternatives were simulated to visualize on basis of actual forest working methods. The options were illustrated as photos produced by computer software. Each alternatives were evaluated by 3 groups with total 593 respondents after reliability test. Visual preference evaluation was used 1 - 10 point rating scale. The ratings were scaled using SBE analysis program of RMRATE. To compare the relationship of visual preference and image scale, Spatial images of 13 thinning alternatives were measured by Semantic differential scale. In general, the respondents preferred refreshing and ordering forest stand after forest working to natural forest stand before forest working. Visual preference decreased with the increasing intensity of bare ground area and slash area in forest stand. And also, visual preference was high related to tree density, clear length of stem, and ground vegetation. Farm line of small clear cutting area was preferred straight line to curve line. Visual preferences were significant differences in certain socioeconomic variables of the respondents. Results indicate how to conduct forest working system for forest scenic beauty management.

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Musical Score Recognition Using Hierarchical ART2 Algorithm (Hierarchical ART2 알고리즘을 이용한 악보 인식)

  • Kim, Kwang-Baek;Woo, Young-Woon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.1997-2003
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    • 2009
  • Methods for effective musical score recognition and efficient editing of musical scores are demanded because functions of computers for researches on musical activities become more and more important parts in recent days. In the conventional methods for handling musical scores manually, there are weak points such as incorrect score symbols in input process and requirement of much time to adjust the incorrect symbols. And also there is another weak point that the scores edited by each application program can be remodified by a specific application program only. In this paper, we proposed a method for automatic musical score recognition of printed musical scores in order to make up for the weak points. In the proposed method, staffs in a scanned score image are eliminated by horizontal histogram, noises are removed by 4 directional edge tracking algorithm, and then musical score symbols are extracted by using Grassfire algorithm. The extracted symbols are recognized by hierarchical ART2 algorithm. In order to evaluate the performance of the proposed method, we used 100 musical scores for experiment. In the experiment, we verified that the proposed method using hierarchical ART2 algorithm is efficient.

3D Model Reconstruction Algorithm Using a Focus Measure Based on Higher Order Statistics (고차 통계 초점 척도를 이용한 3D 모델 복원 알고리즘)

  • Lee, Joo-Hyun;Yoon, Hyeon-Ju;Han, Kyu-Phil
    • Journal of Korea Multimedia Society
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    • v.16 no.1
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    • pp.11-18
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    • 2013
  • This paper presents a SFF(shape from focus) algorithm using a new focus measure based on higher order statistics for the exact depth estimation. Since conventional SFF-based 3D depth reconstruction algorithms used SML(sum of modified Laplacian) as the focus measure, their performance is strongly depended on the image characteristics. These are efficient only for the rich texture and well focused images. Therefore, this paper adopts a new focus measure using HOS(higher order statistics), in order to extract the focus value for relatively poor texture and focused images. The initial best focus area map is generated by the measure. Thereafter, the area refinement, thinning, and corner detection methods are successively applied for the extraction of the locally best focus points. Finally, a 3D model from the carefully selected points is reconstructed by Delaunay triangulation.

Development of a PTV Algorithm for Measuring Sediment-Laden Flows (유사 흐름 측정을 위한 입자추적유속계 알고리듬의 개발)

  • Yu, Kwon-Kyu;Muste, Marian;Ettema, Robert;Yoon, Byung-Man
    • Journal of Korea Water Resources Association
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    • v.38 no.10 s.159
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    • pp.841-849
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    • 2005
  • Two-phase flows, e.g. sediment-laden flow and bubbly flow, have two different flow profiles; flow velocity and sediment velocity. To measure velocity distributions of two-phase flows, it is necessary to use sophisticated instruments which can separate velocity profiles of two-phases. For bubbly flows, PIV (Particle Image Velocimetry) or PTV (Particle Tracking Velocimetry) has given fairly good velocity profiles of two-phases. However, for sediment-laden flows, the applications of PIV or PTV has not been so successful, because the sediment particles introduced to the flow kept the images from being analyzed. A new algorithm, which consists of several image analysis methods, is proposed to analyze sediment-laden flows. For detection algorithm, threshold method, edge detection method, and thinning method are adapted, and for finding matching pair PIV and PTV routines are combined. The proposed method can (1) detect sediment particles with irregular boundaries, (2) remove reflected images and scattered images, and (3) discriminate tracer particles from reflected images of sediment particles.

Vehicle Recognition with Recognition of Vehicle Identification Mark and License Plate (차량 식별마크와 번호판 인식을 통한 차량인식)

  • Lee Eung-Joo;Kim Sung-Jin;Kwon Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.8 no.11
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    • pp.1449-1461
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    • 2005
  • In this paper, we propose a vehicle recognition system based on the classification of vehicle identification mark and recognition of vehicle license plate. In the proposed algorithm, From the input vehicle image, we first simulate preprocessing procedures such as noise reduction, thinning etc., and detect vehicle identification mark and license plate region using the frequency distribution of intensity variation. And then, we classify extracted vehicle candidate region into identification mark, character and number of vehicle by using structural feature informations of vehicle. Lastly, we recognize vehicle informations with recognition of identification mark, character and number of vehicle using hybrid and vertical/horizontal pattern vector method. In the proposed algorithm, we used three properties of vehicle informations such as Independency property, discriminance property and frequency distribution of intensity variation property. In the vehicle images, identification mark is generally independent of the types of vehicle and vehicle identification mark. And also, the license plate region between character and background as well as horizontal/vertical intensity variations are more noticeable than other regions. To show the efficiency of the propofed algorithm, we tested it on 350 vehicle images and found that the propofed method shows good Performance regardless of irregular environment conditions as well as noise, size, and location of vehicles.

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EFFECT OF INDUCTION CHEMOTHERAPY ON FLAP SURVIVAL RATE IN MICROSURGERY (종양수술전 화학요법이 미세수술시 피판생존율에 미치는 영향)

  • Kim, Uk-Kyu;Kim, Yong-Deok;Byun, June-Ho;Shin, Sang-Hun;Chung, In-Kyo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.29 no.6
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    • pp.421-429
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    • 2003
  • Purpose : Neoadjuvant chemotherapy is commonly used to treat cancer patients as adjunct treatment, but if the microvascular tissue transfer is performed simulataneously with cancer resection surgery, the induction chemotherapy might affect the survival rate of vascularized free flap. Our study will focus on the effect of induction chemotherapy on the free flaps which were made on white rat abdomen after injection of 5-FU. Materials and Methods: The experimental rat groups were divided into three groups (total 24 rats) as a normal control group, 24 hrs group after 5-FU injection, 3 days group after 5-FU injection. Inferior abdominal island flaps of 8 Sprague Dawley rats on each group were made and immediately were induced into an ischemic state by clamping the supplying inferior epigastric artery and vein with microvascular clamp for a hour to induce a similiar free flap circumstance, then the inferior abdominal skin flaps were reperfused by releasing the clamps. The flaps on abdomen were repositioned and sutured. The experimental data for flap survival rate was collected by digital photo taking, analysed by computer image program to compare with the flap luminosity. The rats were sacrificed at 3 days, 5 days, 7 days after flap preparation and specimens of the flap were taken and stained with H-E staining. The microscopic finding was made under magnification of 200 and 400. Results: 1. Gross findings on each groups showed the healing condition was good as following sequences; normal, 24 hrs group after chemotherapy, 3 days group after chemotherpy. 2. The values of flap luminosity for evaluation of flap survival rate also showed the same sequences as gross findings of healing state. 3. The microscopic findings of epidermis necrosis, inflammation state, dermis fibrosis, vessel change, fatty tissue layer thinning were compared with each group. The 3 days group after chemotherapy showed remarkably poor healing condition compared to other groups. Conclusion: Chemotherapy agents affected the healing process of free flap, but healing condition was recovered spontaneously as post-injection periods passed out. In opposite to our expectation, 3 days group showed the bad flap condition in comparing with 24 hours group which was considered as immatured body circulation state of chemotherapy agent. It showed that 3 weeks in human being after chemotherapy was not proper as timing of microvascular tissue transfer if 3 days group in rat was considered as same healing period of 3 weeks in human being. More delayed healing timing than 3 weeks might be required in clinical application of free tissue transfer.