• Title/Summary/Keyword: Edge Extraction

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Two-step Boundary Extraction Algorithm with Model (모델 정보를 이용한 2단계 윤곽선 추출 기법)

  • Choe, Hae-Cheol;Lee, Jin-Seong;Jo, Ju-Hyeon;Sin, Ho-Cheol;Kim, Seung-Dae
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.1
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    • pp.49-60
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    • 2002
  • We propose an algorithm for extracting the boundary of a desired object with shape information obtained from sample images. Considering global shape obtained from sample images and edge orientation as well as edge magnitude, the Proposed method composed of two steps finds the boundary of an object. The first step is the approximate segmentation that extracts a rough boundary with a probability map and an edge map. And the second step is the detailed segmentation for finding more accurate boundary based on the SEEL (seed-point extraction and edge linking) algorithm. The experiment results using IR images show robustness to low-quality image and better performance than conventional segmentation methods.

Automatic National Image Interpretability Rating Scales (NIIRS) Measurement Algorithm for Satellite Images (위성영상을 위한 NIIRS(Natinal Image Interpretability Rating Scales) 자동 측정 알고리즘)

  • Kim, Jeahee;Lee, Changu;Park, Jong Won
    • Journal of Korea Multimedia Society
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    • v.19 no.4
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    • pp.725-735
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    • 2016
  • High-resolution satellite images are used in the fields of mapping, natural disaster forecasting, agriculture, ocean-based industries, infrastructure, and environment, and there is a progressive increase in the development and demand for the applications of high-resolution satellite images. Users of the satellite images desire accurate quality of the provided satellite images. Moreover, the distinguishability of each image captured by an actual satellite varies according to the atmospheric environment and solar angle at the captured region, the satellite velocity and capture angle, and the system noise. Hence , NIIRS must be measured for all captured images. There is a significant deficiency in professional human resources and time resources available to measure the NIIRS of few hundred images that are transmitted daily. Currently, NIIRS is measured every few months or even few years to assess the aging of the satellite as well as to verify and calibrate it [3]. Therefore, we develop an algorithm that can measure the national image interpretability rating scales (NIIRS) of a typical satellite image rather than an artificial target satellite image, in order to automatically assess its quality. In this study, the criteria for automatic edge region extraction are derived based on the previous works on manual edge region extraction [4][5], and consequently, we propose an algorithm that can extract the edge region. Moreover, RER and H are calculated from the extracted edge region for automatic edge region extraction. The average NIIRS value was measured to be 3.6342±0.15321 (2 standard deviations) from the automatic measurement experiment on a typical satellite image, which is similar to the result extracted from the artificial target.

A Revised Dynamic ROI Coding Method Based On The Automatic ROI Extraction For Low Depth-of-Field JPEG2000 Images (낮은 피사계 심도 JPEG2000 이미지를 위한 자동 관심영역 추출기반의 개선된 동적 관심영역 코딩 방법)

  • Park, Jae-Heung;Kim, Hyun-Joo;Shim, Jong-Chae;Yoo, Chang-Yeul;Seo, Yeong-Geon;Kang, Ki-Jun
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.10
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    • pp.63-71
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    • 2009
  • In this study, we propose a revised dynamic ROI (Region-of-Interest) coding method in which the focused ROI is automatically extracted without help from users during the recovery process of low DOF (Depth-of-Field) JPEG2000 image. The proposed method creates edge mask information using high frequency sub-band data on a specific level in DWT (Discrete Wavelet Transform), and then identifies the edge code block for a high-speed ROI extraction. The algorithm scans the edge mask data in four directions by the unit of code block and identifies the edge code block simply and fastly using a edge threshold. As the results of experimentation applying for Implicit method, the proposed method showed the superiority in the side of speed and quality comparing to the existing methods.

ENHANCEMENT AND SMOOTHING OF HYPERSPECTAL REMOTE SENSING DATA BY ADVANCED SCALE-SPACE FILTERING

  • Konstantinos, Karantzalos;Demetre, Argialas
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.736-739
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    • 2006
  • While hyperspectral data are very rich in information, their processing poses several challenges such as computational requirements, noise removal and relevant information extraction. In this paper, the application of advanced scale-space filtering to selected hyperspectral bands was investigated. In particular, a pre-processing tool, consisting of anisotropic diffusion and morphological leveling filtering, has been developed, aiming to an edge-preserving smoothing and simplification of hyperspectral data, procedures which are of fundamental importance during feature extraction and object detection. Two scale space parameters define the extent of image smoothing (anisotropic diffusion iterations) and image simplification (scale of morphological levelings). Experimental results demonstrated the effectiveness of the developed scale space filtering for the enhancement and smoothing of hyperspectral remote sensing data and their advantage against watershed over-segmentation problems and edge detection.

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Context-based Video Retrieval using Fast Key Frame Extraction (고속 key frame 추출 기법을 이용한 내용 기반 비디오 검색 기법)

  • Hong, Bo-Hyun;Eum, Min-Young;Kim, Myoung-Ho;Choe, Yoon-Sik
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.539-541
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    • 2005
  • We propose efficient video retrieval scheme which use fast key frame extraction in DCT domain. Our scheme extract key frame using the edge histogram difference which is extracted in compressed domain for I-frames. And the video retrieval is implemented using Hausdorff distance function about edge histogram of key frame. This approach enables fast content-based video retrieval of the compressed video content without decompression process. Experimental results show our scheme is very fast and efficient.

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Biological Image Edge Extraction Based on Adaptive Beamlet Transform

  • Nguyen, Van Hau;Woo, Kyung-Haeng;Choi, Won-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.12 no.2
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    • pp.83-90
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    • 2011
  • In cell biology area, microscopy enables detecting objects inside cells that are stained or fluorescently tagged. It is disadvantageous for observing these objects because of the noisy characteristics of their environmental surrounding. In this paper, a framework is proposed to increase the throughput and reliability for analysis of these images. First, we apply adaptive beamlet transform to extract edges meaningfully followed by orientation, location, and length in different scales. Then, a post-process is implemented to extend and map them onto original image. Our proposed scheme is compared with Canny edge detector and conventional beamlet transform from four evaluation aspects. It produces better results when experiments are conducted on real images. Much better results for observing internal parts make this framework competitive for analysis of cell images.

Detection of eye using optimal edge technique and intensity information (눈 영역에 적합한 에지 추출과 밝기값 정보를 이용한 눈 검출)

  • Mun, Won-Ho;Choi, Yeon-Seok;Kim, Cheol-Ki;Cha, Eui-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.10a
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    • pp.196-199
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    • 2010
  • The human eyes are important facial landmarks for image normalization due to their relatively constant interocular distance. This paper introduces a novel approach for the eye detection task using optimal segmentation method for eye representation. The method consists of three steps: (1)edge extraction method that can be used to accurately extract eye region from the gray-scale face image, (2)extraction of eye region using labeling method, (3)eye localization based on intensity information. Experimental results show that a correct eye detection rate of 98.9% can be achieved on 2408 FERET images with variations in lighting condition and facial expressions.

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Video Segmentation and Key frame Extraction using Multi-resolution Analysis and Statistical Characteristic

  • Cho, Wan-Hyun;Park, Soon-Young;Park, Jong-Hyun
    • Communications for Statistical Applications and Methods
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    • v.10 no.2
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    • pp.457-469
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    • 2003
  • In this paper, we have proposed the efficient algorithm that can segment the video scene change using a various statistical characteristics obtained from by applying the wavelet transformation for each frames. Our method firstly extracts the histogram features from low frequency subband of wavelet-transformed image and then uses these features to detect the abrupt scene change. Second, it extracts the edge information from applying the mesh method to the high frequency subband of transformed image. We quantify the extracted edge information as the values of variance characteristic of each pixel and use these values to detect the gradual scene change. And we have also proposed an algorithm how extract the proper key frame from segmented video scene. Experiment results show that the proposed method is both very efficient algorithm in segmenting video frames and also is to become the appropriate key frame extraction method.

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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