• Title/Summary/Keyword: Local features

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Image Retrieval Using Texture Features BDIP and BVLC (BDIP와 BVCL의 질감특징을 이용한 영상검색)

  • 천영덕;서상용;김남철
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.183-186
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    • 2001
  • In this paper, we first propose new texture features, BVLC (block variation of local correlation coefficients) moments, for content-based image retrieval (CBIR) and then present an image retrieval method based on the fusion of BDIP and BVLC moments. BDIP uses the local probabilities in image blocks to extract valley and edges well. BVLC uses the variations of local correlation coefficients in images blocks to measure texture smoothness well. In order not to be affected with the movement, rotation, and size of an object, the first and second moments of BDIP and BVLC are used for CBIR. Corel DB and Vistex DB are used to evaluate the performance of the proposed retrieval method. Experimental results show that the presented retrieval method yields average 12% better performance than the method using only BDIP or BVLC moments and average 13% better performance than the method using wavelet moments.

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Fingerprint Authentication Based on Minutiae Quandrangle Defined by Neighboring Two Delaunay Triangles (이웃한 두 Delaunay 삼각형이 만드는 특징점 사각형에 기반한 지문 인증)

  • 차순백;조상현;성효경;최홍문
    • Proceedings of the IEEK Conference
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    • 2000.09a
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    • pp.721-724
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    • 2000
  • This paper presents fingerprint authentication method based on minutiae quadrangle definded by neighboring two Delaunay triangles. In this method, we first make minutiae triangle through Delaunay triangulation which adaptively connect neighboring minutiae according to the local minutiae density distribution, and then use feature vectors in authentication which is extracted from the minutiae quadrangle formed by neighboring two minutiae triangles. This prevents the degradation of matching ratio caused by the errors in image processing or local deformation of the fingerprint, and we can authenticate more discriminately as this method reflects wider local area's topological features than the features extracted from the individual minutiae triangles. To evaluate the proposed algorithm's performance, experiment are conducted on 120 fingerprints, of which size is 256 ${\times}$ 364 with 500dpi resolution. Robust authentications are possible with low FRR.

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Local Linear Transform and New Features of Histogram Characteristic Functions for Steganalysis of Least Significant Bit Matching Steganography

  • Zheng, Ergong;Ping, Xijian;Zhang, Tao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.4
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    • pp.840-855
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    • 2011
  • In the context of additive noise steganography model, we propose a method to detect least significant bit (LSB) matching steganography in grayscale images. Images are decomposed into detail sub-bands with local linear transform (LLT) masks which are sensitive to embedding. Novel normalized characteristic function features weighted by a bank of band-pass filters are extracted from the detail sub-bands. A suboptimal feature set is searched by using a threshold selection algorithm. Extensive experiments are performed on four diverse uncompressed image databases. In comparison with other well-known feature sets, the proposed feature set performs the best under most circumstances.

Image Segmentation Using the Locally Adaptive Fuzzy C-means Algorithm (국부적응 Fuzzy C-means 알고리듬을 이용한 영상분할)

  • 최우영;박래홍;이상욱
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.6
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    • pp.680-687
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    • 1988
  • When only global or local features of images are considered, the segmented results exhibit inevitable errors. To reduce these errors, first we divide the image into uniform and nonuniform regions by considering the local properties of the image. Next we obtain the segmented results by applying the Fuzzy C-means (FCM) algorithm to the picture and determining to which uniform reigons each pixel of the nonuniform regions belongs. To reduce the computational burden and memory required for the FCM algorithm, the equations used for FCM algorithm are modified. The performance of the proposed method is quantitatively compared to existing ones using only global or local features of the picture. Computer simualtion result shows that the segmented results obtained by applying the proposed method are superior to existing ones.

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Smoke Detection System Research using Fully Connected Method based on Adaboost

  • Lee, Yeunghak;Kim, Taesun;Shim, Jaechang
    • Journal of Multimedia Information System
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    • v.4 no.2
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    • pp.79-82
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    • 2017
  • Smoke and fire have different shapes and colours. This article suggests a fully connected system which is used two features using Adaboost algorithm for constructing a strong classifier as linear combination. We calculate the local histogram feature by gradient and bin, local binary pattern value, and projection vectors for each cell. According to the histogram magnitude, this paper applied adapted weighting value to improve the recognition rate. To preserve the local region and shape feature which has edge intensity, this paper processed the normalization sequence. For the extracted features, this paper Adaboost algorithm which makes strong classification to classify the objects. Our smoke detection system based on the proposed approach leads to higher detection accuracy than other system.

Discriminative Training of Sequence Taggers via Local Feature Matching

  • Kim, Minyoung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.14 no.3
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    • pp.209-215
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    • 2014
  • Sequence tagging is the task of predicting frame-wise labels for a given input sequence and has important applications to diverse domains. Conventional methods such as maximum likelihood (ML) learning matches global features in empirical and model distributions, rather than local features, which directly translates into frame-wise prediction errors. Recent probabilistic sequence models such as conditional random fields (CRFs) have achieved great success in a variety of situations. In this paper, we introduce a novel discriminative CRF learning algorithm to minimize local feature mismatches. Unlike overall data fitting originating from global feature matching in ML learning, our approach reduces the total error over all frames in a sequence. We also provide an efficient gradient-based learning method via gradient forward-backward recursion, which requires the same computational complexity as ML learning. For several real-world sequence tagging problems, we empirically demonstrate that the proposed learning algorithm achieves significantly more accurate prediction performance than standard estimators.

Multi-feature local sparse representation for infrared pedestrian tracking

  • Wang, Xin;Xu, Lingling;Ning, Chen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.3
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    • pp.1464-1480
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    • 2019
  • Robust tracking of infrared (IR) pedestrian targets with various backgrounds, e.g. appearance changes, illumination variations, and background disturbances, is a great challenge in the infrared image processing field. In the paper, we address a new tracking method for IR pedestrian targets via multi-feature local sparse representation (SR), which consists of three important modules. In the first module, a multi-feature local SR model is constructed. Considering the characterization of infrared pedestrian targets, the gray and edge features are first extracted from all target templates, and then fused into the model learning process. In the second module, an effective tracker is proposed via the learned model. To improve the computational efficiency, a sliding window mechanism with multiple scales is first used to scan the current frame to sample the target candidates. Then, the candidates are recognized via sparse reconstruction residual analysis. In the third module, an adaptive dictionary update approach is designed to further improve the tracking performance. The results demonstrate that our method outperforms several classical methods for infrared pedestrian tracking.

Assessment of Local Tumor Progression After Image-Guided Thermal Ablation for Renal Cell Carcinoma

  • Byung Kwan Park
    • Korean Journal of Radiology
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    • v.25 no.1
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    • pp.33-42
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    • 2024
  • Focal enhancement typically suggests local tumor progression (LTP) after renal cell carcinoma is percutaneously ablated. However, evaluating findings that are false positive or negative of LTP is less familiar to radiologists who have little experience with renal ablation. Various imaging features are encountered during and after thermal ablation. Ablation procedures and previous follow-up imaging should be reviewed before determining if there is LTP. Previous studies have focused on detecting the presence or absence of focal enhancement within the ablation zone. Therefore, various diagnostic pitfalls can be experienced using computed tomography or magnetic resonance imaging examinations. This review aimed to assess how to read images during or after ablation procedures, recognize imaging features of LTP and determine factors that influence LTP.

Content-based Image Retrieval Using Texture Features Extracted from Local Energy and Local Correlation of Gabor Transformed Images

  • Bu, Hee-Hyung;Kim, Nam-Chul;Lee, Bae-Ho;Kim, Sung-Ho
    • Journal of Information Processing Systems
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    • v.13 no.5
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    • pp.1372-1381
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    • 2017
  • In this paper, a texture feature extraction method using local energy and local correlation of Gabor transformed images is proposed and applied to an image retrieval system. The Gabor wavelet is known to be similar to the response of the human visual system. The outputs of the Gabor transformation are robust to variants of object size and illumination. Due to such advantages, it has been actively studied in various fields such as image retrieval, classification, analysis, etc. In this paper, in order to fully exploit the superior aspects of Gabor wavelet, local energy and local correlation features are extracted from Gabor transformed images and then applied to an image retrieval system. Some experiments are conducted to compare the performance of the proposed method with those of the conventional Gabor method and the popular rotation-invariant uniform local binary pattern (RULBP) method in terms of precision vs recall. The Mahalanobis distance is used to measure the similarity between a query image and a database (DB) image. Experimental results for Corel DB and VisTex DB show that the proposed method is superior to the conventional Gabor method. The proposed method also yields precision and recall 6.58% and 3.66% higher on average in Corel DB, respectively, and 4.87% and 3.37% higher on average in VisTex DB, respectively, than the popular RULBP method.

Local Appearance-based Face Recognition Using SVM and PCA (SVM과 PCA를 이용한 국부 외형 기반 얼굴 인식 방법)

  • Park, Seung-Hwan;Kwak, No-Jun
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.3
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    • pp.54-60
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    • 2010
  • The local appearance-based method is one of the face recognition methods that divides face image into small areas and extracts features from each area of face image using statistical analysis. It collects classification results of each area and decides identity of a face image using a voting scheme by integrating classification results of each area of a face image. The conventional local appearance-based method divides face images into small pieces and uses all the pieces in recognition process. In this paper, we propose a local appearance-based method that makes use of only the relatively important facial components. The proposed method detects the facial components such as eyes, nose and mouth that differs much from person to person. In doing so, the proposed method detects exact locations of facial components using support vector machines (SVM). Based on the detected facial components, a number of small images that contain the facial parts are constructed. Then it extracts features from each facial component image using principal components analysis (PCA). We compared the performance of the proposed method to those of the conventional methods. The results show that the proposed method outperforms the conventional local appearance-based method while preserving the advantages of the conventional local appearance-based method.