• Title/Summary/Keyword: Segmentation and feature extraction

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An Efficient Feature Point Detection for Interactive Pen-Input Display Applications (인터액티브 펜-입력 디스플레이 애플리케이션을 위한 효과적인 특징점 추출법)

  • Kim Dae-Hyun;Kim Myoung-Jun
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.11_12
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    • pp.705-716
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    • 2005
  • There exist many feature point detection algorithms that developed in pattern recognition research . However, interactive applications for the pen-input displays such as Tablet PCs and LCD tablets have set different goals; reliable segmentation for different drawing styles and real-time on-the-fly fieature point defection. This paper presents a curvature estimation method crucial for segmenting freeHand pen input. It considers only local shape descriptors, thus, peforming a novel curvature estimation on-the-fly while drawing on a pen-input display This has been used for pen marking recognition to build a 3D sketch-based modeling application.

Text Location and Extraction for Business Cards Using Stroke Width Estimation

  • Zhang, Cheng Dong;Lee, Guee-Sang
    • International Journal of Contents
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    • v.8 no.1
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    • pp.30-38
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    • 2012
  • Text extraction and binarization are the important pre-processing steps for text recognition. The performance of text binarization strongly related to the accuracy of recognition stage. In our proposed method, the first stage based on line detection and shape feature analysis applied to locate the position of a business card and detect the shape from the complex environment. In the second stage, several local regions contained the possible text components are separated based on the projection histogram. In each local region, the pixels grouped into several connected components based on the connected component labeling and projection histogram. Then, classify each connect component into text region and reject the non-text region based on the feature information analysis such as size of connected component and stroke width estimation.

Extraction and Shape Description of Feature Region on Ocular Fundus Fluorescein Angiogram (형광 안저화상에 관한 특수 영역의 유출 및 모양)

  • Go, Chang-Rim;Ha, Yeong-Ho;Kim, Su-Jung
    • Journal of Biomedical Engineering Research
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    • v.8 no.1
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    • pp.81-86
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    • 1987
  • An image feature extraction method for the low contrast fluoresceln angiogram in dlabetes was studied. To obtain effective image segmentation, an adaptive local difference image is generated and relaxation process are applied to this difference Image. By the use of distance transformed data with segmented image, shape and location of feature regions were obtained. It was shown that the location and shape descriptions of Impaired blood vessel networks and retinal regions are can he utilized for the diagnosis of diabetes and other disease.

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The Recognition of Korean Character Using Preceding Layer Driven MLP (Preceding Layer Driven 다층 퍼셉트론을 이용한 한글문자 인식)

  • 백승엽;김동훈;정호선
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.28B no.5
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    • pp.382-393
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    • 1991
  • In this paper, we propose a method for recognizing printed Korean characters using the Preceding Layer Driven multi-layer perceptron. The new learning algorithm which assigns the weight values to an integer and makes use of the transfer function as the step function was presented to design the hardware. We obtained 522 Korean character-image as an experimental object through scanner with 600DPI resolution. The preprocessing for feature extraction of Korean character is the separation of individual character, noise elimination smoothing, thinnig, edge point extraction, branch point extraction, and stroke segmentation. The used feature data are the number of edge points and their shapes, the number of branch points, and the number of strokes with 8 directions.

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A Comparative Performance Analysis of Segmentation Models for Lumbar Key-points Extraction (요추 특징점 추출을 위한 영역 분할 모델의 성능 비교 분석)

  • Seunghee Yoo;Minho Choi ;Jun-Su Jang
    • Journal of Biomedical Engineering Research
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    • v.44 no.5
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    • pp.354-361
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    • 2023
  • Most of spinal diseases are diagnosed based on the subjective judgment of a specialist, so numerous studies have been conducted to find objectivity by automating the diagnosis process using deep learning. In this paper, we propose a method that combines segmentation and feature extraction, which are frequently used techniques for diagnosing spinal diseases. Four models, U-Net, U-Net++, DeepLabv3+, and M-Net were trained and compared using 1000 X-ray images, and key-points were derived using Douglas-Peucker algorithms. For evaluation, Dice Similarity Coefficient(DSC), Intersection over Union(IoU), precision, recall, and area under precision-recall curve evaluation metrics were used and U-Net++ showed the best performance in all metrics with an average DSC of 0.9724. For the average Euclidean distance between estimated key-points and ground truth, U-Net was the best, followed by U-Net++. However the difference in average distance was about 0.1 pixels, which is not significant. The results suggest that it is possible to extract key-points based on segmentation and that it can be used to accurately diagnose various spinal diseases, including spondylolisthesis, with consistent criteria.

Block Classification of Document Images Using the Spatial Gray Level Dependence Matrix (SGLDM을 이용한 문서영상의 블록 분류)

  • Kim Joong-Soo
    • Journal of Korea Multimedia Society
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    • v.8 no.10
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    • pp.1347-1359
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    • 2005
  • We propose an efficient block classification of the document images using the second-order statistical texture features computed from spatial gray level dependence matrix (SGLDM). We studied on the techniques that will improve the block speed of the segmentation and feature extraction speed and the accuracy of the detailed classification. In order to speedup the block segmentation, we binarize the gray level image and then segmented by applying smoothing method instead of using texture features of gray level images. We extracted seven texture features from the SGLDM of the gray image blocks and we applied these normalized features to the BP (backpropagation) neural network, and classified the segmented blocks into the six detailed block categories of small font, medium font, large font, graphic, table, and photo blocks. Unlike the conventional texture classification of the gray level image in aerial terrain photos, we improve the classification speed by a single application of the texture discrimination mask, the size of which Is the same as that of each block already segmented in obtaining the SGLDM.

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Automatic Segmentation of Cellular Images for High-Throughput Genome-Wide RNA Interference Screening (고속 Genome-Wide RNA 간섭 스크리닝을 위한 세포영상의 자동 분할)

  • Han, Chan-Hee;Song, In-Hwan;Lee, Si-Woong
    • The Journal of the Korea Contents Association
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    • v.10 no.4
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    • pp.19-27
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    • 2010
  • In recent years, high-throughput genome-wide RNA interference screening is emerging as an essential tool to biologists in understanding complex cellular processes. The manual analysis of the large number of images produced in each study spends much time and the labor. Hence, automatic cellular image analysis becomes an urgent need, where segmentation is the first and one of the most important steps. However, those factors such as the region overlapping, a variety of shapes, and non-uniform local characteristics of cellular images become obstacles to efficient cell segmentation. To avoid the problem, a new watershed-based cell segmentation algorithm using a localized segmentation method and a feature vector is proposed in this paper. Localized approach in segmentation resolves the problems caused by a variety of shapes and non-uniform characteristics. In addition, the poor performance of segmentation in overlapped regions can be improved by taking advantage of a feature vector whose component features complement each other. Simulation results show that the proposed method improves the segmentation performance compared to the method in Cellprofiler.

A Study on Optimal Shape-Size Index Extraction for Classification of High Resolution Satellite Imagery (고해상도 영상의 분류결과 개선을 위한 최적의 Shape-Size Index 추출에 관한 연구)

  • Han, You-Kyung;Kim, Hye-Jin;Choi, Jae-Wan;Kim, Yong-Il
    • Korean Journal of Remote Sensing
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    • v.25 no.2
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    • pp.145-154
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    • 2009
  • High spatial resolution satellite image classification has a limitation when only using the spectral information due to the complex spatial arrangement of features and spectral heterogeneity within each class. Therefore, the extraction of the spatial information is one of the most important steps in high resolution satellite image classification. This study proposes a new spatial feature extraction method, named SSI(Shape-Size Index). SSI uses a simple region-growing based image segmentation and allocates spatial property value in each segment. The extracted feature is integrated with spectral bands to improve overall classification accuracy. The classification is achieved by applying a SVM(Support Vector Machines) classifier. In order to evaluate the proposed feature extraction method, KOMPSAT-2 and QuickBird-2 data are used for experiments. It is demonstrated that proposed SSI algorithm leads to a notable increase in classification accuracy.

Content-based Image Retrieval using Feature Extraction in Wavelet Transform Domain (웨이브릿 변환 영역에서 특징추출을 이용한 내용기반 영상 검색)

  • 최인호;이상훈
    • Journal of Korea Multimedia Society
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    • v.5 no.4
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    • pp.415-425
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    • 2002
  • In this paper, we present a content-based image retrieval method which is based on the feature extraction in the wavelet transform domain. In order to overcome the drawbacks of the feature vector making up methods which use the global wavelet coefficients in subbands, we utilize the energy value of wavelet coefficients, and the shape-based retrieval of objects is processed by moment which is invariant in translation, scaling, rotation of the objects The proposed methods reduce feature vector size, and make progress performance of classification retrieval which provides fast retrievals times. To offer the abilities of region-based image retrieval, we discussed the image segmentation method which can reduce the effect of an irregular light sources. The image segmentation method uses a region-merging, and candidate regions which are merged were selected by the energy values of high frequency bands in discrete wavelet transform. The region-based image retrieval is executed by using the segmented region information, and the images are retrieved by a color, texture, shape feature vector.

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Aerial Scene Labeling Based on Convolutional Neural Networks (Convolutional Neural Networks기반 항공영상 영역분할 및 분류)

  • Na, Jong-Pil;Hwang, Seung-Jun;Park, Seung-Je;Baek, Joong-Hwan
    • Journal of Advanced Navigation Technology
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    • v.19 no.6
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    • pp.484-491
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    • 2015
  • Aerial scene is greatly increased by the introduction and supply of the image due to the growth of digital optical imaging technology and development of the UAV. It has been used as the extraction of ground properties, classification, change detection, image fusion and mapping based on the aerial image. In particular, in the image analysis and utilization of deep learning algorithm it has shown a new paradigm to overcome the limitation of the field of pattern recognition. This paper presents the possibility to apply a more wide range and various fields through the segmentation and classification of aerial scene based on the Deep learning(ConvNet). We build 4-classes image database consists of Road, Building, Yard, Forest total 3000. Each of the classes has a certain pattern, the results with feature vector map come out differently. Our system consists of feature extraction, classification and training. Feature extraction is built up of two layers based on ConvNet. And then, it is classified by using the Multilayer perceptron and Logistic regression, the algorithm as a classification process.