• Title/Summary/Keyword: Local-feature

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Efficient Iris Recognition using Deep-Learning Convolution Neural Network (딥러닝 합성곱 신경망을 이용한 효율적인 홍채인식)

  • Choi, Gwang-Mi;Jeong, Yu-Jeong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.15 no.3
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    • pp.521-526
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    • 2020
  • This paper presents an improved HOLP neural network that adds 25 average values to a typical HOLP neural network using 25 feature vector values as input values by applying high-order local autocorrelation function, which is excellent for extracting immutable feature values of iris images. Compared with deep learning structures with different types, we compared the recognition rate of iris recognition using Back-Propagation neural network, which shows excellent performance in voice and image field, and synthetic product neural network that integrates feature extractor and classifier.

Robust-to-rotation Iris Recognition Using Local Gradient Orientation Histogram (국부적 그래디언트 방향 히스토그램을 이용한 회전에 강인한 홍채 인식)

  • Choi, Chang-Soo;Jun, Byoung-Min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.3C
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    • pp.268-273
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    • 2009
  • Iris recognition is a biometric technology which can identify a person using the iris pattern. It is important for the iris recognition system to extract the feature which is invariant to changes in iris patterns. Those changes can be occurred by the influence of lights, changes in the size of the pupil, and head tilting. In this paper, we propose a novel method based on local gradient orientation histogram which is robust to variations in illumination and rotations of iris patterns. The proposed method enables high-speed feature extraction and feature comparison because it requires no additional processing to obtain the rotation invariance, and shows comparable performance to the well-known previous methods.

An Improved Texture Feature Extraction Method for Recognizing Emphysema in CT Images

  • Peng, Shao-Hu;Nam, Hyun-Do
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.11
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    • pp.30-41
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    • 2010
  • In this study we propose a new texture feature extraction method based on an estimation of the brightness and structural uniformity of CT images representing the important characteristics for emphysema recognition. The Center-Symmetric Local Binary Pattern (CS-LBP) is first used to combine gray level in order to describe the brightness uniformity characteristics of the CT image. Then the gradient orientation difference is proposed to generate another CS-LBP code combining with gray level to represent the structural uniformity characteristics of the CT image. The usage of the gray level, CS-LBP and gradient orientation differences enables the proposed method to extract rich and distinctive information from the CT images in multiple directions. Experimental results showed that the performance of the proposed method is more stable with respect to sensitivity and specificity when compared with the SGLDM, GLRLM and GLDM. The proposed method outperformed these three conventional methods (SGLDM, GLRLM, and GLDM) 7.85[%], 22.87[%], and 16.67[%] respectively, according to the diagnosis of average accuracy, demonstrated by the Receiver Operating Characteristic (ROC) curves.

Content-based Image Retrieval using LBP and HSV Color Histogram (LBP와 HSV 컬러 히스토그램을 이용한 내용 기반 영상 검색)

  • Lee, Kwon;Lee, Chulhee
    • Journal of Broadcast Engineering
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    • v.18 no.3
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    • pp.372-379
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    • 2013
  • In this paper, we proposed a content-based image retrieval algorithm using local binary patterns and HSV color histogram. Images are retrieved using image input in image retrieval system. Many researches are based on global feature distribution such as color, texture and shape. These techniques decrease the retrieval performance in images which contained background the large amount of image. To overcome this drawback, the proposed method extract background fast and emphasize the feature of object by shrinking the background. The proposed method uses HSV color histogram and Local Binary Patterns. We also extract the Local Binary Patterns in quantized Hue domain. Experimental results show that the proposed method 82% precision using Corel 1000 database.

Robust Facial Expression Recognition Based on Signed Local Directional Pattern (Signed Local Directional Pattern을 이용한 강력한 얼굴 표정인식)

  • Ryu, Byungyong;Kim, Jaemyun;Ahn, Kiok;Song, Gihun;Chae, Oksam
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.6
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    • pp.89-101
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    • 2014
  • In this paper, we proposed a new local micro pattern, Signed Local Directional Pattern(SLDP). SLDP uses information of edges to represent the face's texture. This can produce a more discriminating and efficient code than other state-of-the-art methods. Each micro pattern of SLDP is encoded by sign and its major directions in which maximum edge responses exist-which allows it to distinguish among similar edge patterns that have different intensity transitions. In this paper, we divide the face image into several regions, each of which is used to calculate the distributions of the SLDP codes. Each distribution represents features of the region and these features are concatenated into a feature vector. We carried out facial expression recognition with feature vectors and SVM(Support Vector Machine) on Cohn-Kanade and JAFFE databases. SLDP shows better classification accuracy than other existing methods.

A study on a local descriptor and entropy-based similarity measure for object recognition system being robust to local illumination change (지역적 밝기 변화에 강인한 물체 인식을 위한 지역 서술자와 엔트로피 기반 유사도 척도에 관한 연구)

  • Yang, Jeong-Eun;Yang, Seung-Yong;Hong, Seok-Keun;Cho, Seok-Je
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.9
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    • pp.1112-1118
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    • 2014
  • In this paper, we propose a local descriptor and a similarity measure that is robust to radiometic variations. The proposed local descriptor is made up Haar wavelet filter and it can contain frequency informations about the feature point and its surrounding pixels in fixed region, and it is able to describe feature point clearly under ununiform illumination condition. And a proposed similarity measure is combined with conventional entropy-based similarity and another similarities that is generated by local descriptor. It can reflect similarities between image regions accurately under radiometic illumination variations. We validate with experimental results on some images and we confirm that the proposed algorithm is more superior than conventional algorithms.

Face Detection Using Edge Orientation Map and Local Color Information (에지 방향 지도와 영역 컬러 정보를 이용한 얼굴 추출 기법)

  • Kim, Jae-Hyup;Moon, Young-Shik
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.987-990
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    • 2005
  • An important issue in the field of face recognitions and man-machine interfaces is an automatic detection of faces in visual scenes. it should be computationally fast enough to allow an online detection. In this paper we describe our ongoing work on face detection that models the face appearance by edge orientation and color distribution. We show that edge orientation is a powerful feature to describe objects like faces. We present a method for face region detection using edge orientation and a method for face feature detection using local color information. We demonstrate the capability of our detection method on an image database of 1877 images taken from more than 700 people. The variations in head size, lighting and background are considerable, and all images are taken using low-end cameras. Experimental results show that the proposed scheme achieves 94% detection rate with a resonable amount of computation time.

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Vector space based augmented structural kinematic feature descriptor for human activity recognition in videos

  • Dharmalingam, Sowmiya;Palanisamy, Anandhakumar
    • ETRI Journal
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    • v.40 no.4
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    • pp.499-510
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    • 2018
  • A vector space based augmented structural kinematic (VSASK) feature descriptor is proposed for human activity recognition. An action descriptor is built by integrating the structural and kinematic properties of the actor using vector space based augmented matrix representation. Using the local or global information separately may not provide sufficient action characteristics. The proposed action descriptor combines both the local (pose) and global (position and velocity) features using augmented matrix schema and thereby increases the robustness of the descriptor. A multiclass support vector machine (SVM) is used to learn each action descriptor for the corresponding activity classification and understanding. The performance of the proposed descriptor is experimentally analyzed using the Weizmann and KTH datasets. The average recognition rate for the Weizmann and KTH datasets is 100% and 99.89%, respectively. The computational time for the proposed descriptor learning is 0.003 seconds, which is an improvement of approximately 1.4% over the existing methods.

Improved Gradient Direction Assisted Linking Algorithm for Linear Feature Extraction in High Resolution Satellite Images, an Iterative Dynamic Programming Approach

  • Yang, Kai;Liew, Soo Chin;Lee, Ken Yoong;Kwoh, Leong Keong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.408-410
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    • 2003
  • In this paper, an improved gradient direction assisted linking algorithm is proposed. This algorithm begins with initial seeds satisfying some local criteria. Then it will search along the direction provided by the initial point. A window will be generated in the gradient direction of the current point. Instead of the conventional method which only considers the value of the local salient structure, an improved mathematical model is proposed to describe the desired linear features. This model not only considers the value of the salient structure but also the direction of it. Furthermore, the linking problem under this model can be efficiently solved by dynamic programming method. This algorithm is tested for linear features detection in IKONOS images. The result demonstrates this algorithm is quite promising.

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Point Pattern Matching Algorithm Using Unit-Circle Parametrization

  • Choi, Nam-Seok;Lee, Byung-Gook;Lee, Joon-Jae
    • Journal of Korea Multimedia Society
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    • v.13 no.6
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    • pp.825-832
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    • 2010
  • This paper presents only a matching algorithm based on Delaunay triangulation and Parametrization from the extracted minutiae points. This method maps local neighborhood of points of two different point sets to unit-circle using topology information by Delaunay triangulation method from feature points of real fingerprint. Then, a linked convex polygon that includes an interior point is constructed as one-ring which is mapped to unit-circle using Parametrization that keep shape preserve. In local matching, each area of polygon in unit-circle is compared. If the difference of two areas are within tolerance, two polygons are consider to be matched and then translation, rotation and scaling factors for global matching are calculated.