• Title/Summary/Keyword: Local feature

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A Study on Video Data Protection Method based on MPEG using Dynamic Shuffling (동적 셔플링을 이용한 MPEG기반의 동영상 암호화 방법에 관한 연구)

  • Lee, Ji-Bum;Lee, Kyoung-Hak;Ko, Hyung-Hwa
    • Journal of Korea Multimedia Society
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    • v.10 no.1
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    • pp.58-65
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    • 2007
  • This dissertation proposes digital video protection algorithm lot moving image based on MPEG. Shuffling-based encryption algorithms using a fixed random shuffling table are quite simple and effective but vulnerable to the chosen plaintext attack. To overcome this problem, it is necessary to change the key used for generation of the shuffling table. However, this may pose a significant burden on the security key management system. A better approach is to generate the shuffling table based on the local feature of an image. In order to withstand the chosen plaintext attack, at first, we propose a interleaving algorithm that is adaptive to the local feature of an image. Secondly, using the multiple shuffling method which is combined interleaving with existing random shuffling method, we encrypted the DPCM processed 8*8 blocks. Experimental results showed that the proposed algorithm needs only 10% time of SEED encryption algorithm and moreover there is no overhead bit. In video sequence encryption, multiple random shuffling algorithms are used to encrypt the DC and AC coefficients of intra frame, and motion vector encryption and macroblock shuffling are used to encrypt the intra-coded macroblock in predicted frame.

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Illumination Robust Feature Descriptor Based on Exact Order (조명 변화에 강인한 엄격한 순차 기반의 특징점 기술자)

  • Kim, Bongjoe;Sohn, Kwanghoon
    • Journal of Broadcast Engineering
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    • v.18 no.1
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    • pp.77-87
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    • 2013
  • In this paper, we present a novel method for local image descriptor called exact order based descriptor (EOD) which is robust to illumination changes and Gaussian noise. Exact orders of image patch is induced by changing discrete intensity value into k-dimensional continuous vector to resolve the ambiguity of ordering for same intensity pixel value. EOD is generated from overall distribution of exact orders in the patch. The proposed local descriptor is compared with several state-of-the-art descriptors over a number of images. Experimental results show that the proposed method outperforms many state-of-the-art descriptors in the presence of illumination changes, blur and viewpoint change. Also, the proposed method can be used for many computer vision applications such as face recognition, texture recognition and image analysis.

A Design Study of the Mountainous Contemporary Han-ok based on Regional Tradition in Gangwon-do (지역적 전통에 기반을 둔 강원도 산간형 현대한옥 계획 연구)

  • Kim, Do-Kyoung;Choi, Sung-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2789-2796
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    • 2012
  • The purpose of this study was to develope the Contemporary Han-ok based on the natural environment characteristics of mountainous territory in Gangwon-do. According to the result of this study, Eco-friendly Contemporary Han-ok adaptable to the natural environment feature focused on the local climate was proposed based on the tradition of mountainous territory housing in Gangwon-do. In addition, proposed Mountainous Han-ok in Gangwon-do planned to keep the out feature of traditional Korean Han-ok and have the environmental control system same as traditional Korean Han-ok. Despite of several limits, this study has the meaning in terms of propose the prototype of adaptable contemporary han-ok based on the Natural Environment Characteristics of Mountainous Territory and regional tradition in Gangwon-do in cognition of local natural environment difference. the proposal of contemporary han-ok as the result of this study will give a support to the wide planning of Han-ok and the development plan of contemporary Han-ok.

Robust Face and Facial Feature Tracking in Image Sequences (연속 영상에서 강인한 얼굴 및 얼굴 특징 추적)

  • Jang, Kyung-Shik;Lee, Chan-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.9
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    • pp.1972-1978
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    • 2010
  • AAM(Active Appearance Model) is one of the most effective ways to detect deformable 2D objects and is a kind of mathematical optimization methods. The cost function is a convex function because it is a least-square function, but the search space is not convex space so it is not guaranteed that a local minimum is the optimal solution. That is, if the initial value does not depart from around the global minimum, it converges to a local minimum, so it is difficult to detect face contour correctly. In this study, an AAM-based face tracking algorithm is proposed, which is robust to various lighting conditions and backgrounds. Eye detection is performed using SIFT and Genetic algorithm, the information of eye are used for AAM's initial matching information. Through experiments, it is verified that the proposed AAM-based face tracking method is more robust with respect to pose and background of face than the conventional basic AAM-based face tracking method.

Image Retrieval Using Combination of Color and Multiresolution Texture Features (칼라 및 다해상도 질감 특징 결합에 의한 영상검색)

  • Chun Young-deok;Sung Joong-ki;Kim Nam-chul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9C
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    • pp.930-938
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    • 2005
  • We propose a content-based image retrieval(CBIR) method based on an efncient combination of a color feature and multiresolution texture features. As a color feature, a HSV autocorrelograrn is chosen which is blown to measure spatial correlation of colors well. As texture features, BDIP and BVLC moments are chosen which is hewn to measure local intensity variations well and measure local texture smoothness well, respectively. The texture features are obtained in a wavelet pyramid of the luminance component of a color image. The extracted features are combined for efficient similarity computation by the normalization depending on their dimensions and standard deviation vectors. Experimental results show that the proposed method yielded average $8\%\;and\;11\%$ better performance in precision vs. recall than the method using BDIPBVLC moments and the method using color autocorrelograrn, respectively and yielded at least $10\%$ better performance than the methods using wavelet moments, CSD, color histogram. Specially, the proposed method shows an excellent performance over the other methods in image DBs contained images of various resolutions.

Texture Descriptor for Texture-Based Image Retrieval and Its Application in Computer-Aided Diagnosis System (질감 기반 이미지 검색을 위한 질감 서술자 및 컴퓨터 조력 진단 시스템의 적용)

  • Saipullah, Khairul Muzzammil;Peng, Shao-Hu;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.47 no.4
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    • pp.34-43
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    • 2010
  • Texture information plays an important role in object recognition and classification. To perform an accurate classification, the texture feature used in the classification must be highly discriminative. This paper presents a novel texture descriptor for texture-based image retrieval and its application in Computer-Aided Diagnosis (CAD) system for Emphysema classification. The texture descriptor is based on the combination of local surrounding neighborhood difference and centralized neighborhood difference and is named as Combined Neighborhood Difference (CND). The local differences of surrounding neighborhood difference and centralized neighborhood difference between pixels are compared and converted into binary codewords. Then binomial factor is assigned to the codewords in order to convert them into high discriminative unique values. The distribution of these unique values is computed and used as the texture feature vectors. The texture classification accuracies using Outex and Brodatz dataset show that CND achieves an average of 92.5%, whereas LBP, LND and Gabor filter achieve 89.3%, 90.7% and 83.6%, respectively. The implementations of CND in the computer-aided diagnosis of Emphysema is also presented in this paper.

Task Reconstruction Method for Real-Time Singularity Avoidance for Robotic Manipulators : Dynamic Task Priority Based Analysis (로봇 매니플레이터의 실시간 특이점 회피를 위한 작업 재구성법: 동적 작업 우선도에 기초한 해석)

  • 김진현;최영진
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.10
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    • pp.855-868
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    • 2004
  • There are several types of singularities in controlling robotic manipulators: kinematic singularity, algorithmic singularity, semi-kinematic singularity, semi-algorithmic singularity, and representation singularity. The kinematic and algorithmic singularities have been investigated intensively because they are not predictable or difficult to avoid. The problem with these singularities is an unnecessary performance reduction in non-singular region and the difficulty in performance tuning. Tn this paper, we propose a method of avoiding kinematic and algorithmic singularities by applying a task reconstruction approach while maximizing the task performance by calculating singularity measures. The proposed method is implemented by removing the component approaching the singularity calculated by using singularity measure in real time. The outstanding feature of the proposed task reconstruction method (TR-method) is that it is based on a local task reconstruction as opposed to the local joint reconstruction of many other approaches. And, this method has dynamic task priority assignment feature which ensures the system stability under singular regions owing to the change of task priority. The TR-method enables us to increase the task controller gain to improve the task performance whereas this increase can destabilize the system for the conventional algorithms in real experiments. In addition, the physical meaning of tuning parameters is very straightforward. Hence, we can maximize task performance even near the singular region while simultaneously obtaining the singularity-free motion. The advantage of the proposed method is experimentally tested by using the 7-dof spatial manipulator, and the result shows that the new method improves the performance several times over the existing algorithms.

Effective Mood Classification Method based on Music Segments (부분 정보에 기반한 효과적인 음악 무드 분류 방법)

  • Park, Gun-Han;Park, Sang-Yong;Kang, Seok-Joong
    • Journal of Korea Multimedia Society
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    • v.10 no.3
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    • pp.391-400
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    • 2007
  • According to the recent advances in multimedia computing, storage and searching technology have made large volume of music contents become prevalent. Also there has been increasing needs for the study on efficient categorization and searching technique for music contents management. In this paper, a new classifying method using the local information of music content and music tone feature is proposed. While the conventional classifying algorithms are based on entire information of music content, the algorithm proposed in this paper focuses on only the specific local information, which can drastically reduce the computing time without losing classifying accuracy. In order to improve the classifying accuracy, it uses a new classification feature based on music tone. The proposed method has been implemented as a part of MuSE (Music Search/Classification Engine) which was installed on various systems including commercial PDAs and PCs.

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A Stereo Matching Based on A Genetic Algorithm Using A Multi-resolution Method and AD-Census (다해상도 가법과 AD-Census를 이용한 유전 알고리즘 기반의 스테레오 정합)

  • Hong, Seok-Keun;Cho, Seok-Je
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.1
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    • pp.12-18
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    • 2012
  • Stereo correspondence is the central problem of stereo vision. In this paper, we propose a stereo matching scheme based on a genetic algorithm using a multi-resolution method and AD-Census. The proposed approach considers the matching environment as an optimization problem and finds the disparity by using a genetic algorithm And adaptive chronosome structure using edge pixels and crossover mechanism are employed in this technique. A cost function is composes of certain constraints whice are commonly used in stereo matching. AD-Census measure is applied to reduce disparity error. To increase the efficiency of process, we apply image pyramid method to stereo matching and calculate the initial disparity map at the coarsest resolution. Then initial disparity map is propagated to the next finer resolution, interpolated and performed disparity refinement using local feature vector. We valid our method not only reduces the search time for correspondence compared with conventional GA-based method but also ensures the validity of matching.

Feature Extraction and Classification of High Dimensional Biomedical Spectral Data (고차원을 갖는 생체 스펙트럼 데이터의 특징추출 및 분류기법)

  • Cho, Jae-Hoon;Park, Jin-Il;Lee, Dae-Jong;Chun, Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.3
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    • pp.297-303
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    • 2009
  • In this paper, we propose the biomedical spectral pattern classification techniques by the fusion scheme based on the SpPCA and MLP in extended feature space. A conventional PCA technique for the dimension reduction has the problem that it can't find an optimal transformation matrix if the property of input data is nonlinear. To overcome this drawback, we extract features by the SpPCA technique in extended space which use the local patterns rather than whole patterns. In the classification step, individual classifier based on MLP calculates the similarity of each class for local features. Finally, biomedical spectral patterns is classified by the fusion scheme to effectively combine the individual information. As the simulation results to verify the effectiveness, the proposed method showed more improved classification results than conventional methods.