• Title/Summary/Keyword: edge histogram

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Contents-based Image Retrieval Using Color & Edge Information (칼라와 에지 정보를 이용한 내용기반 영상 검색)

  • Park, Dong-Won;An, Syungog;Ma, Ming;Singh, Kulwinder
    • The Journal of Korean Association of Computer Education
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    • v.8 no.1
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    • pp.81-91
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    • 2005
  • In this paper we present a novel approach for image retrieval using color and edge information. We take into account the HSI(Hue, Saturation and Intensity) color space instead of RGB space, which emphasizes more on visual perception. In our system colors in an image are clustered into a small number of representative colors. The color feature descriptor consists of the representative colors and their percentages in the image. An improved cumulative color histogram distance measure is defined for this descriptor. And also, we have developed an efficient edge detection technique as an optional feature to our retrieval system in order to surmount the weakness of color feature. During the query processing, both the features (color, edge information) could be integrated for image retrieval as well as a standalone entity, by specifying it in a certain proportion. The content-based retrieval system is tested to be effective in terms of retrieval and scalability through experimental results and precision-recall analysis.

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Reduced-Reference Quality Assessment for Compressed Videos Based on the Similarity Measure of Edge Projections (에지 투영의 유사도를 이용한 압축된 영상에 대한 Reduced-Reference 화질 평가)

  • Kim, Dong-O;Park, Rae-Hong;Sim, Dong-Gyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.45 no.3
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    • pp.37-45
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    • 2008
  • Quality assessment ai s to evaluate if a distorted image or video has a good quality by measuring the difference between the original and distorted images or videos. In this paper, to assess the visual qualify of a distorted image or video, visual features of the distorted image are compared with those of the original image instead of the direct comparison of the distorted image with the original image. We use edge projections from two images as features, where the edge projection can be easily obtained by projecting edge pixels in an edge map along vertical/horizontal direction. In this paper, edge projections are obtained by using vertical/horizontal directions of gradients as well as the magnitude of each gradient. Experimental results show the effectiveness of the proposed quality assessment through the comparison with conventional quality assessment algorithms such as structural similarity(SSIM), edge peak signal-to-noise ratio(EPSNR), and edge histogram descriptor(EHD) methods.

Medical Image Enhancement Using an Adaptive Nonlinear Histogram Stretching (적응적 비선형 히스트그램 스트레칭을 이용한 의료영상의 화질향상)

  • Kim, Seung-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.1
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    • pp.658-665
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    • 2015
  • In the production of medical images, noise reduction and contrast enhancement are important methods to increase qualities of processing results. By using the edge-based denoising and adaptive nonlinear histogram stretching, a novel medical image enhancement algorithm is proposed. First, a medical image is decomposed by wavelet transform, and then all high frequency sub-images are decomposed by Haar transform. At the same time, edge detection with Sobel operator is performed. Second, noises in all high frequency sub-images are reduced by edge-based soft-threshold method. Third, high frequency coefficients are further enhanced by adaptive weight values in different sub-images. Finally, an adaptive nonlinear histogram stretching method is applied to increase the contrast of resultant image. Experimental results show that the proposed algorithm can enhance a low contrast medical image while preserving edges effectively without blurring the details.

Fast Edge Map Method And Edge Map Compression Using Edge Features (고속 Edge Map 생성 방법과 Edge 특성을 이용한 Edge Map 압축)

  • Kim, Do-Hyun;Kim, Yoon
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2015.07a
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    • pp.45-48
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    • 2015
  • 오늘날 하드웨어의 발전으로 인해 영상 해상도는 FHD를 넘어 4K UHD 이상의 영상 해상도가 사용화되고 있다. 하지만 Edge Map을 만들기 위해 일반적으로 사용하는 함수들은 Convolution 함수 일종으로서 영상의 해상도가 높을수록 더 많은 Complexity를 요구한다. 또한 현재 주요 영상 압축 기술인 JPEG, H.264/AVC High efficiency video coding(HEVC)같은 기법들은 자연 영상을 중점으로 개발되어 있어 Edge map 압축에 있어 자연 영상만큼의 효율을 보여주지 못하고 있다. 본 논문은 원 영상을 Down Scaling한 뒤 이미지를 다시 원래 사이즈로 Up Scaling하여 두 영상의 차를 이용한 Edge Map을 생성하는 새로운 방법을 소개한다. 생성된 Edge Map의 특성인 Histogram 값의 분포가 0을 중심으로 Gaussian 분포를 가지는 것을 이용한 Zero Based 코덱을 제안한다. 제안된 알고리즘을 이용하여 고 해상도 영상에서도 빠르게 Edge Map을 생성하고 제안한 코덱을 통해 해당 Edge map을 압축한 결과 다른 압축 기술보다 더 뛰어난 성능을 보여주었다.

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Image Contrast Enhancement Based on a Multi-Cue Histogram

  • Lee, Sung-Ho;Zhang, Dongni;Ko, Sung-Jea
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.5
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    • pp.349-353
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    • 2015
  • The conventional intensity histogram does not indicate edge information, which is important in the perception of image contrast. In this paper, we propose a multi-cue histogram (MCH) to represent a collaborative distribution of both the intensity and the edges of an image. Based on the MCH, if the intensity values have high frequency and a large gradient magnitude, they are spread into a larger dynamic range. Otherwise, the intensity values are not strongly stretched. As a result, image details, such as edges and textures, can be enhanced while artifacts and noise can be prevented, as demonstrated in the experimental results.

Entropic Image Thresholding Segmentation Based on Gabor Histogram

  • Yi, Sanli;Zhang, Guifang;He, Jianfeng;Tong, Lirong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.2113-2128
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    • 2019
  • Image thresholding techniques introducing spatial information are widely used image segmentation. Some methods are used to calculate the optimal threshold by building a specific histogram with different parameters, such as gray value of pixel, average gray value and gradient-magnitude, etc. However, these methods still have some limitations. In this paper, an entropic thresholding method based on Gabor histogram (a new 2D histogram constructed by using Gabor filter) is applied to image segmentation, which can distinguish foreground/background, edge and noise of image effectively. Comparing with some methods, including 2D-KSW, GLSC-KSW, 2D-D-KSW and GLGM-KSW, the proposed method, tested on 10 realistic images for segmentation, presents a higher effectiveness and robustness.

Edge-based Method for Human Detection in an Image (영상 내 사람의 검출을 위한 에지 기반 방법)

  • Do, Yongtae;Ban, Jonghee
    • Journal of Sensor Science and Technology
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    • v.25 no.4
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    • pp.285-290
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    • 2016
  • Human sensing is an important but challenging technology. Unlike other methods for sensing humans, a vision sensor has many advantages, and there has been active research in automatic human detection in camera images. The combination of Histogram of Oriented Gradients (HOG) and Support Vector Machine (SVM) is currently one of the most successful methods in vision-based human detection. However, extracting HOG features from an image is computer intensive, and it is thus hard to employ the HOG method in real-time processing applications. This paper describes an efficient solution to this speed problem of the HOG method. Our method obtains edge information of an image and finds candidate regions where humans very likely exist based on the distribution pattern of the detected edge points. The HOG features are then extracted only from the candidate image regions. Since complex HOG processing is adaptively done by the guidance of the simpler edge detection step, human detection can be performed quickly. Experimental results show that the proposed method is effective in various images.

Extraction of Features in key frames of News Video for Content-based Retrieval (내용 기반 검색을 위한 뉴스 비디오 키 프레임의 특징 정보 추출)

  • Jung, Yung-Eun;Lee, Dong-Seop;Jeon, Keun-Hwan;Lee, Yang-Weon
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.9
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    • pp.2294-2301
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    • 1998
  • The aim of this paper is to extract features from each news scenes for example, symbol icon which can be distinct each broadcasting corp, icon and caption which are has feature and important information for the scene in respectively, In this paper, we propose extraction methods of caption that has important prohlem of news videos and it can be classified in three steps, First of al!, we converted that input images from video frame to YIQ color vector in first stage. And then, we divide input image into regions in clear hy using equalized color histogram of input image, In last, we extracts caption using edge histogram based on vertical and horizontal line, We also propose the method which can extract news icon in selected key frames by the difference of inter-histogram and can divide each scene by the extracted icon. In this paper, we used comparison method of edge histogram instead of complex methcxls based on color histogram or wavelet or moving objects, so we shorten computation through using simpler algorithm. and we shown good result of feature's extraction.

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Histogram-based road border line extractor for road extraction from satellite imagery (위성영상에서 도로 추출을 위한 히스토그램 기반 경계선 추출자)

  • Lee, Dong-Hoon;Kim, Jong-Hwa;Choi, Heung-Moon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.5
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    • pp.28-34
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    • 2007
  • A histogram-based road border line extractor is proposed for an efficient road extraction from the high-resolution satellite imagery. The road border lines are extracted from an edge strength map based on the directional histogram difference between the road and the non-road region. The straight and the curved roads are extracted hierarchically from the edge strength map of the original image and the segmented road cluster images, and the road network is constructed based on the connectivity. Unlike the conventional approaches based on the spectral similarity, the proposed road extraction method is more robust to noise because it extracts roads based on the histogram, and is able to extract both the location and the width of roads. In addition, the proposed method can extract roads with various spectral characteristics by identifying the road clusters automatically. Experimental results on IKONOS multi-spectral satellite imagery with high spatial resolution show that the proposed method can extract the straight and the curved roads as well as the accurate road border lines.

Integrating Color, Texture and Edge Features for Content-Based Image Retrieval (내용기반 이미지 검색을 위한 색상, 텍스쳐, 에지 기능의 통합)

  • Ma Ming;Park Dong-Won
    • Science of Emotion and Sensibility
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    • v.7 no.4
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    • pp.57-65
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    • 2004
  • In this paper, we present a hybrid approach which incorporates color, texture and shape in content-based image retrieval. Colors in each image are clustered into a small number of representative colors. The feature descriptor consists of the representative colors and their percentages in the image. A similarity measure similar to the cumulative color histogram distance measure is defined for this descriptor. The co-occurrence matrix as a statistical method is used for texture analysis. An optimal set of five statistical functions are extracted from the co-occurrence matrix of each image, in order to render the feature vector for eachimage maximally informative. The edge information captured within edge histograms is extracted after a pre-processing phase that performs color transformation, quantization, and filtering. The features where thus extracted and stored within feature vectors and were later compared with an intersection-based method. The content-based retrieval system is tested to be effective in terms of retrieval and scalability through experimental results and precision-recall analysis.

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