• Title/Summary/Keyword: Histogram

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An Improved Histogram-Based Image Hash (Histogram에 기반한 Image Hash 개선)

  • Kim, So-Young;Kim, Hyoung-Joong
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.531-534
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    • 2008
  • Image Hash specifies as a descriptor that can be used to measure similarity in images. Among all image Hash methods, histogram based image Hash has robustness to common noise-like operation and various geometric except histogram _equalization. In this_paper an improved histogram based Image Hash that is using "Imadjust" filter I together is proposed. This paper has achieved a satisfactory performance level on histogram equalization as well as geometric deformation.

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Content-Based Image Retrieval using Histogram Area Calculation (히스토그램 영역계산을 이용한 내용기반 영상검색)

  • Park, Min-Sheik;Yoo, Gi-Hyoung;Kwak, Hoon-Sung
    • Journal of the Korea Computer Industry Society
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    • v.6 no.2
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    • pp.265-270
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    • 2005
  • Histogram is very sensitive in lighting because of feature between color space. When it has intensity of moved light, It may be possibility that similarity drop down, So In this paper, introduce new image retrieval method that calls HAC (Histogram Area Calculation). This method divides area of Histogram by a few area and calculate areas. The proposed method is to calculate area of Histogram and compare similarity based on feature that histogram has presently. Performance of our proposed method was verified more excellent than other Conventional method and Merged Color Histogram.

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Obstacle a voidance using VFH (Vector Field Histogram) in four legged robot (VFH(Vector Field Histogram)을 이용한 4족 로봇의 장애물 회피)

  • Jung, Hyun-Ryong;Kim, Young-Bae
    • Proceedings of the KIEE Conference
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    • 2003.11b
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    • pp.23-26
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    • 2003
  • The vector field histogram(VFH) uses a two-dimensional Cartesian histogram grid as a world model. The VFH method subsequently employs a two-stage data-reduction process in order to compute the desired control commands for the vehicle. In the first stage the histogram grid is reduced to a one dimensional polar histogram that is constructed around the robot's momentary location. Each sector in the polar histogram contains a value representing the polar obstacle density in that direction. In the second stage, the algorithm selects the most suitable sector from among all polar histogram sectors with a low polar obstacle density, and the steering of the robot is aligned with that direction. We applied this algorithm to our four-legged robot.

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Content-Based Image Retrieval Using Adaptive Color Histogram

  • Yoo Gi-Hyoung;Park Jung-Man;You Kang-Soo;Yoo Seung-Sun;Kwak Hoon-Sung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.9C
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    • pp.949-954
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    • 2005
  • From the 90's, the image information retrieval methods have been on progress. As good examples of the methods, Conventional histogram method and merged-color histogram method were introduced. Dey could get good result in image retrieval. However, Conventional histogram method has disadvantages if the histogram is shifted as a result of intensity change. Merged-color histogram, also, causes more process so, it needs more time to retrieve images. In this paper, we propose an improved new method using Adaptive Color Histogram(ACH) in image retrieval. The proposed method has been tested and verified through a number of simulations using hundreds of images in a database. The simulation results have quickly yielded the highly accurate candidate images in comparison to other retrieval methods. We show that ACH's can give superior results to color histograms for image retrieval.

Multiresolution Histogram Specification Method in The Spatial Domain for Image Enhancement (영상 개선을 위한 공간 영역에서의 다해상도 히스토그램 지정 기법)

  • Park, Se-Hyuk;Huh, Kyung-Moo
    • Proceedings of the IEEK Conference
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    • 2009.05a
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    • pp.169-171
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    • 2009
  • The histogram specification is to change the histogram shape of the image into the already defined shape. This technique can be applied usefully in various image processing fields which include a machine vision. However, the histogram specification technique has its basic limits. For example, the histogram does not have location information of pixel within the image and receives the digital image, which is stored through a quantization process, as an input. Namely, the accuracy of specification falls in the high-resolution image because the larger the resolution of image is becoming, the more the pixels having similar value are becoming. Therefore, we proposed the multiresolution histogram specification method for improving the accuracy of specification. Consequently, we can know that if the histogram specification is accomplished by using the proposed algorithm, destination image and source image were changed almost similarly.

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Obstacle avoidance using Vector Field Histogram in simulation (Vector Field Histogram를 이용한 장애물 회피 시뮬레이션)

  • 정현룡;김영배
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1076-1079
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    • 2003
  • The vector field histogram(VFH) uses a two-dimensional Cartesian histogram grid as a world model. The VFH method subsequently employs a two-stage data-reduction process in order to compute the desired control commands for the vehicle. In the first stage the histogram grid is reduced to a one dimensional polar histogram that is constructed around the robot's momentary location. Each sector in the polar histogram contains a value representing the polar obstacle density in that direction. In the second stage, the algorithm selects the most suitable sector from among all polar histogram sectors with a low polar obstacle density, and the steering of the robot is aligned with that direction. We applied this algorithm to our simulation program and tested..

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An Improvement of Histogram Equalization Using Edge Information of an Image (영상 에지 정보를 이용한 히스토그램 평활화 기법의 개선)

  • Yun, Jong Seob;Kim, Jin Heon
    • Journal of Korea Multimedia Society
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    • v.20 no.2
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    • pp.188-195
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    • 2017
  • The paper presents a histogram equalization method using the edge information of an image to be processed. The basic idea of this method is to carry out histogram equalization with edge information, which is important and essential for object conformation. In the proposed method, the edge information is used to generate histogram for the equalization process. It is found to be effective to suppress the histogram spikes that cause quantum jumps in mapping function for the equalization process. The proposed method is tested for randomly selected 30 images and compared to conventional approaches with a quantitative measure to check it preserves the structural similarity. Experimental results show that the proposed method has better performance and no artifacts caused by histogram spikes.

Local-Based Iterative Histogram Matching for Relative Radiometric Normalization

  • Seo, Dae Kyo;Eo, Yang Dam
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.37 no.5
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    • pp.323-330
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    • 2019
  • Radiometric normalization with multi-temporal satellite images is essential for time series analysis and change detection. Generally, relative radiometric normalization, which is an image-based method, is performed, and histogram matching is a representative method for normalizing the non-linear properties. However, since it utilizes global statistical information only, local information is not considered at all. Thus, this paper proposes a histogram matching method considering local information. The proposed method divides histograms based on density, mean, and standard deviation of image intensities, and performs histogram matching locally on the sub-histogram. The matched histogram is then further partitioned and this process is performed again, iteratively, controlled with the wasserstein distance. Finally, the proposed method is compared to global histogram matching. The experimental results show that the proposed method is visually and quantitatively superior to the conventional method, which indicates the applicability of the proposed method to the radiometric normalization of multi-temporal images with non-linear properties.

A Image Contrast Enhancement by Clustering of Image Histogram (영상의 히스토그램 군집화에 의한 영상 대비 향상)

  • Hong, Seok-Keun;Lee, Ki-Hwan;Cho, Seok-Je
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.4
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    • pp.239-244
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    • 2009
  • Image contrast enhancement has an important role in image processing applications. Conventional contrast enhancement techniques, histogram stretching and histogram equalization, and many methods based on histogram equalization often fail to produce satisfactory results for broad variety of low-contrast images. So, this paper proposes a new image contrast enhancement method based on the clustering method. The number of cluster of histogram is found by analysing the histogram of original image. The histogram components is classified using K-means algorithm. And then these histogram components are performed histogram stretching and histogram equalization selectively by comparing cluster range with pixel rate of cluster. From the expremental results, the proposed method was more effective than conventional contrast enhancement techniques.

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Fuzzy histogram in estimating loss distributions for operational risk (운영 위험 관련 손실 분포 - 퍼지 히스토그램의 효과)

  • Pak, Ro-Jin
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.4
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    • pp.705-712
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    • 2009
  • Histogram is the oldest and most widely used density estimator for presentation and exploration of observed univariate data. The structure of a histogram really depends on the number of bins and the width of the bins, so that slight changes on bins can produce totally different shape of a histogram. In order to solve this problem the fuzzy histogram was introduced and the result was good enough (Loquin and Strauss, 2008). In particular, when estimating loss distribution related with operational risk a histogram has been widely used. In this article, instead of an ordinary histogram we try to use a fuzzy histogram for estimating loss distribution and show that a fuzzy histogram provide more stable results.

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