• 제목/요약/키워드: image analysis algorithm

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영상처리 기술 비교 (Comparison of Image Procesing Technique)

  • 신성윤;이양원
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2010년도 제42차 하계학술발표논문집 18권2호
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    • pp.149-150
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    • 2010
  • This paper contains some simple daily used and research used complex methods, describe their theories and analysis implement results, for deeper comprehension. After that, take an actual application of car license location, elaborate the common algorithm responsibility, and meanwhile take some subtle new attempts for algorithm development.

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3D Non-Rigid Registration for Abdominal PET-CT and MR Images Using Mutual Information and Independent Component Analysis

  • Lee, Hakjae;Chun, Jaehee;Lee, Kisung;Kim, Kyeong Min
    • IEIE Transactions on Smart Processing and Computing
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    • 제4권5호
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    • pp.311-317
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    • 2015
  • The aim of this study is to develop a 3D registration algorithm for positron emission tomography/computed tomography (PET/CT) and magnetic resonance (MR) images acquired from independent PET/CT and MR imaging systems. Combined PET/CT images provide anatomic and functional information, and MR images have high resolution for soft tissue. With the registration technique, the strengths of each modality image can be combined to achieve higher performance in diagnosis and radiotherapy planning. The proposed method consists of two stages: normalized mutual information (NMI)-based global matching and independent component analysis (ICA)-based refinement. In global matching, the field of view of the CT and MR images are adjusted to the same size in the preprocessing step. Then, the target image is geometrically transformed, and the similarities between the two images are measured with NMI. The optimization step updates the transformation parameters to efficiently find the best matched parameter set. In the refinement stage, ICA planes from the windowed image slices are extracted and the similarity between the images is measured to determine the transformation parameters of the control points. B-spline. based freeform deformation is performed for the geometric transformation. The results show good agreement between PET/CT and MR images.

Utilizing Principal Component Analysis in Unsupervised Classification Based on Remote Sensing Data

  • Lee, Byung-Gul;Kang, In-Joan
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2003년도 International Symposium on Clean Environment
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    • pp.33-36
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    • 2003
  • Principal component analysis (PCA) was used to improve image classification by the unsupervised classification techniques, the K-means. To do this, I selected a Landsat TM scene of Jeju Island, Korea and proposed two methods for PCA: unstandardized PCA (UPCA) and standardized PCA (SPCA). The estimated accuracy of the image classification of Jeju area was computed by error matrix. The error matrix was derived from three unsupervised classification methods. Error matrices indicated that classifications done on the first three principal components for UPCA and SPCA of the scene were more accurate than those done on the seven bands of TM data and that also the results of UPCA and SPCA were better than those of the raw Landsat TM data. The classification of TM data by the K-means algorithm was particularly poor at distinguishing different land covers on the island. From the classification results, we also found that the principal component based classifications had characteristics independent of the unsupervised techniques (numerical algorithms) while the TM data based classifications were very dependent upon the techniques. This means that PCA data has uniform characteristics for image classification that are less affected by choice of classification scheme. In the results, we also found that UPCA results are better than SPCA since UPCA has wider range of digital number of an image.

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도시환경의 이미지 및 시각적 선호도에 관한 연구 -도시 업무용 건물의 외부공간을 중심으로- (The Image and Visual Preference for Urban Setting : Focused on Outdoor Spaces of Urban Office Buildings)

  • 이선화;김유일;서주환
    • 한국조경학회지
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    • 제26권3호
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    • pp.134-142
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    • 1998
  • THe purpose of this study is to suggest the major determinants of visual preference in the outdoor spaces of urban office buildings. For this, the spatial image was analyzed by the factor analysis algorithm. The level of visual preferences was measured by a slide simulation test, and these data were analyzed by the multiple regressioni. The result of this study can be summarized as follows; Factors covering the spatial image were found to be 'mystery','changeability','coherence' and 'legibility'. T.V. was obtained as 58.4%. Outdoor spaces of urban office buildings were classified into four groups by the multi dimensional scaling method. As for the analysis of imageability in each spatial type, the factor scores of measuring high values were different for all types. Type II, IV obtained higher rank of visual preference and type III, I obtained lower. For all types, the factors of visual preference were found to be 'mystery','changeability','coherence' and 'legibility'. The visual preference determinants of urban setting focused on outdoor spaces of urban office buildings may be the major factors which must be considered in planning and designing as the functional basis for the quantitative analysis.

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단백질 2-DE 이미지 분석에서 정확한 스팟 매칭 패턴 검색을 위한 효과적인 방법 (An Efficient Method to Find Accurate Spot-matching Patterns in Protein 2-DE Image Analysis)

  • 김연화;이원석
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제16권5호
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    • pp.551-555
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    • 2010
  • 단백질 2-DE 이미지 분석에서 단백질 자체가 가지고 있는 불안정성과 2-DE 실험이 가지고 있는 근본적인 문제점으로 인하여 이미지 스팟 매칭 분석의 정확도가 낮아지게 된다. 이 논문에서는 다중 참조이미지를 사용하여, 스팟 매칭 패턴의 정확도에 큰 영향을 주는 이미지 찌그러짐을 보완하고, 그에 따른 노이즈 스팟 제거와 참조 이미지 품질에 의한 정확도 저하를 최소화하는 방법을 제안하였다. 또한 2-DE 이미지의 데이터 특성에 의하여 이미지 수가 증가할 때 성능이 급격히 떨어지는 문제를 해결하기 위하여, 다중 참조이미지를 사용하여 구축한 스팟 매칭 데이터베이스를 이미지의 생물학적 특성에 의하여 "분할 및 확장" 방법을 사용하여, 정확도를 향상시키는 동시에 패턴 길이를 보장하는 스팟 매칭 패턴을 효과적으로 생성하였다. 실험에서는 실제 인간 2-DE 이미지 데이터를 사용하여 제안한 방법의 타당성을 보여준다.

Improved Contrast for Threshold Random-grid-based Visual Cryptography

  • Hu, Hao;Shen, Gang;Fu, Zhengxin;Yu, Bin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권7호
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    • pp.3401-3420
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    • 2018
  • Pixel expansion and contrast are two major performance parameters for visual cryptography scheme (VCS), which is a type of secret image sharing. Random Grid (RG) is an alternative approach to solve the pixel expansion problem. Chen and Tsao proposed the first (k, n) RG-based VCS, and then Guo et al., Wu et al., Shyu, and Yan et al. significantly improved the contrast in recent years. However, the investigations on improving the contrast of threshold RG-based VCS are not sufficient. In this paper, we develop a contrast-improved algorithm for (k, n) RG-based VCS. Theoretical analysis and experimental results demonstrate that the proposed algorithm outperformers the previous threshold algorithms with better visual quality and a higher accuracy of contrast.

이진 영상에서의 단순화된 윤곽선 추출 방법 (Extraction of Simplified Boundary In Binary Image)

  • 김성영
    • 한국컴퓨터정보학회논문지
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    • 제4권4호
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    • pp.34-39
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    • 1999
  • 본 논문에서는 이진 영상에서 경계에 발생하는 잡영을 효율적으로 제거하고 형상을 단순화시켜 윤곽선을 추출할 수 있는 방법을 제안하였다. 제안된 방법은 이진 영상에서 영역의 윤곽선을 구하는 기존의 $2{times}2$ 마스크 사용 방법을 일부 수정하여 한 픽셀 두께의 잡영을 효율적으로 제거할 수 있도록 하였다. 이를 위해 영역 경계의 잡영에서는 윤곽선 추적 경로가 중복되는 특성과 잡영의 끝점에서의 추적 특성을 분석하여 이용하였다. 또한 흰색 바탕을 윤곽선 추출에 활용함으로써 본래의 형상을 유지하며 효과적으로 단순화된 윤곽선 추출 결과를 얻을 수 있도록 하였다. 제안된 방법은 다양한 실험을 통해 그 효용성을 확인하였다.

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A Face-Detection Postprocessing Scheme Using a Geometric Analysis for Multimedia Applications

  • Jang, Kyounghoon;Cho, Hosang;Kim, Chang-Wan;Kang, Bongsoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제13권1호
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    • pp.34-42
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    • 2013
  • Human faces have been broadly studied in digital image and video processing fields. An appearance-based method, the adaptive boosting learning algorithm using integral image representations has been successfully employed for face detection, taking advantage of the feature extraction's low computational complexity. In this paper, we propose a face-detection postprocessing method that equalizes instantaneous facial regions in an efficient hardware architecture for use in real-time multimedia applications. The proposed system requires low hardware resources and exhibits robust performance in terms of the movements, zooming, and classification of faces. A series of experimental results obtained using video sequences collected under dynamic conditions are discussed.

비젼 데이타를 이용한 아크 용접로보트의 용접선 추적에 관한 연구 (A Study on Seam Tracking for Robotic Arc Welding Using Snapshot Visual Data)

  • 김은엽;김광수
    • 대한산업공학회지
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    • 제18권2호
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    • pp.83-97
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    • 1992
  • A new approach, to seam tracking for robotic are welding is proposed. In this approach, the weld model is a snapshot image and the acquired image is analyzed and compared to the welding database which contains CAD data, weld positions, weld parameters, etc. This paper presents a fast and robust algorithm for the Hough Transform. This modified Hough Transform(MHT) algorithm uses the least-squares regression analysis method in order to approximate the edge lines more precisely, and leads to a significant reduction in both computation and storage. In comparison with the conventional seam tracking methods, this new approach has the advantages of low cost, continuous welding, and various type welding.

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Encryption-based Image Steganography Technique for Secure Medical Image Transmission During the COVID-19 Pandemic

  • Alkhliwi, Sultan
    • International Journal of Computer Science & Network Security
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    • 제21권3호
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    • pp.83-93
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    • 2021
  • COVID-19 poses a major risk to global health, highlighting the importance of faster and proper diagnosis. To handle the rise in the number of patients and eliminate redundant tests, healthcare information exchange and medical data are transmitted between healthcare centres. Medical data sharing helps speed up patient treatment; consequently, exchanging healthcare data is the requirement of the present era. Since healthcare professionals share data through the internet, security remains a critical challenge, which needs to be addressed. During the COVID-19 pandemic, computed tomography (CT) and X-ray images play a vital part in the diagnosis process, constituting information that needs to be shared among hospitals. Encryption and image steganography techniques can be employed to achieve secure data transmission of COVID-19 images. This study presents a new encryption with the image steganography model for secure data transmission (EIS-SDT) for COVID-19 diagnosis. The EIS-SDT model uses a multilevel discrete wavelet transform for image decomposition and Manta Ray Foraging Optimization algorithm for optimal pixel selection. The EIS-SDT method uses a double logistic chaotic map (DLCM) is employed for secret image encryption. The application of the DLCM-based encryption procedure provides an additional level of security to the image steganography technique. An extensive simulation results analysis ensures the effective performance of the EIS-SDT model and the results are investigated under several evaluation parameters. The outcome indicates that the EIS-SDT model has outperformed the existing methods considerably.