• 제목/요약/키워드: image of science

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Reversible data hiding algorithm using spatial locality and the surface characteristics of image

  • Jung, Soo-Mok;On, Byung-Won
    • 한국컴퓨터정보학회논문지
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    • 제21권8호
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    • pp.1-12
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    • 2016
  • In this paper, we propose a very efficient reversible data hiding algorithm using spatial locality and the surface characteristics of image. Spacial locality and a variety of surface characteristics are present in natural images. So, it is possible to precisely predict the pixel value using the locality and surface characteristics of image. Therefore, the frequency is increased significantly at the peak point of the difference histogram using the precisely predicted pixel values. Thus, it is possible to increase the amount of data to be embedded in image using the spatial locality and surface characteristics of image. By using the proposed reversible data hiding algorithm, visually high quality stego-image can be generated, the embedded data and the original cover image can be extracted without distortion from the stego-image, and the embedding data are much greater than that of the previous algorithm. The experimental results show the superiority of the proposed algorithm.

디지털 자동 초점을 위한 등방성 점확산함수 추정 (Estimation of Circularly Symmetric Point Spread Function for Digital Auto-Focusing)

  • 김동균;박영욱;이진희;백준기
    • 대한전자공학회논문지SP
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    • 제46권1호
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    • pp.7-13
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    • 2009
  • 본 논문은 디지털 자동초점을 위한 등방성 점확산함수 추정에 관한 새로운 방법을 제안한다. 제안하는 알고리듬은 영상의 윤곽에서 방향을 판단하고 방향에 따라 윤곽 프로파일을 수집한다. 수집한 윤곽 프로파일을 평균하여 계단응답을 만들고 등방성 점확산함수의 특징을 이용하여 점확산함수를 추정한다. 실험을 통해 열화된 영상에서 제안하는 알고리듬으로 점확산함수를 추정하는 과정을 보이고 정확성을 증명한다.

Can Coffee Shops That Have Become the Red Ocean Win with ESG?

  • KWAK, Min-Kyu;CHA, Seong-Soo
    • 유통과학연구
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    • 제20권3호
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    • pp.83-93
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    • 2022
  • Purpose: This study aims to investigate the relationship between ESG activities (Environment, Social, Governance) of coffee shops and their brand image, purchase intention. Research design, data and methodology: To test the hypothesis, a survey was conducted for about one month from May to June, 2021, and a total of 311 people responded to the survey, and the responses from 311 copies were used for the analysis. Validity and reliability analysis were performed, and the relationship between latent variables was empirically analyzed using the structural equation modelling. Results: The results of the study are as follows. First, among the ESG activities of coffee shops, the environmental and social sectors had a significant positive (+) effect on the brand image, but the governance aspect showed no significant effect on the brand image. Second, it was found that the symbolic image and the empirical image had a significant positive (+) effect on the purchase intention, but the functional image did not have a significant effect on the purchase intention. Conclusions: The results of this study suggest that as the number of coffee shops and the heated competition are increasing, it is possible to build a differentiated brand image through ESG activities rather than relying on the functions and services of competing products.

KNN-based Image Annotation by Collectively Mining Visual and Semantic Similarities

  • Ji, Qian;Zhang, Liyan;Li, Zechao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권9호
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    • pp.4476-4490
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    • 2017
  • The aim of image annotation is to determine labels that can accurately describe the semantic information of images. Many approaches have been proposed to automate the image annotation task while achieving good performance. However, in most cases, the semantic similarities of images are ignored. Towards this end, we propose a novel Visual-Semantic Nearest Neighbor (VS-KNN) method by collectively exploring visual and semantic similarities for image annotation. First, for each label, visual nearest neighbors of a given test image are constructed from training images associated with this label. Second, each neighboring subset is determined by mining the semantic similarity and the visual similarity. Finally, the relevance between the images and labels is determined based on maximum a posteriori estimation. Extensive experiments were conducted using three widely used image datasets. The experimental results show the effectiveness of the proposed method in comparison with state-of-the-arts methods.

영상정보를 이용한 돼지의 비접촉 체중계측시스템 인자 구명 (Identification of Discrimination Factors for a Pig Noncontact Weighing System Using Image Data)

  • 장동일;임영일;임정택;장요한;장홍희
    • 한국축산시설환경학회지
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    • 제5권2호
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    • pp.93-100
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    • 1999
  • Pig's original image data was transformed to a binary image, an image excluding head and tail portion from the whole binary image, and a projected image associated with pig's height. Then the length of body, width of shoulder, and area of pig were calculated and the relationships among the above characteristics and pig's weight were analyzed. The results obtained from this study were as follows: 1. Whole binary image data was considered to be improper to determine the pig's weight because the movement of pig's head and tail portion affected the image data. 2. Binary image data excluding head and tail portion from the whole binary image showed a better estimation of the pig's weight than the whole binary image. 3. Pig's should width was analyzed to be improper factor to determine the pig's weight. 4. The projected image associated with pig's height showed the highest correlation between the pig's area of the image and pig's weight(R2=0.9965). From this research the projected image associated with pig's height, which is excluding head and tail portion from the whole body of pig's image, was considered to be the prime factor to measure the pig's weight by the noncontact measurement.

행렬 분해와 공격자 구조를 이용한 비밀이미지 공유 기법 (Secret Image Sharing Scheme using Matrix Decomposition and Adversary Structure)

  • 현승일;신상호;유기영
    • 한국멀티미디어학회논문지
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    • 제17권8호
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    • pp.953-960
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    • 2014
  • In Shamir's (t,n)-threshold based secret image sharing schemes, there exists a problem that the secret image can be reconstructed when an arbitrary attacker becomes aware of t secret image pieces, or t participants are malicious collusion. It is because that utilizes linear combination polynomial arithmetic operation. In order to overcome the problem, we propose a secret image sharing scheme using matrix decomposition and adversary structure. In the proposed scheme, there is no reconstruction of the secret image even when an arbitrary attacker become aware of t secret image pieces. Also, we utilize a simple matrix decomposition operation in order to improve the security of the secret image. In experiments, we show that performances of embedding capacity and image distortion ratio of the proposed scheme are superior to previous schemes.

Automatic Estimation of Spatially Varying Focal Length for Correcting Distortion in Fisheye Lens Images

  • Kim, Hyungtae;Kim, Daehee;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • 제2권6호
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    • pp.339-344
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    • 2013
  • This paper presents an automatic focal length estimation method to correct the fisheye lens distortion in a spatially adaptive manner. The proposed method estimates the focal length of the fisheye lens by generating two reference focal lengths. The distorted fisheye lens image is finally corrected using the orthographic projection model. The experimental results showed that the proposed focal length estimation method is more accurate than existing methods in terms of the loss rate.

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Multi-Focus Image Fusion Using Transformation Techniques: A Comparative Analysis

  • Ali Alferaidi
    • International Journal of Computer Science & Network Security
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    • 제23권4호
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    • pp.39-47
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    • 2023
  • This study compares various transformation techniques for multifocus image fusion. Multi-focus image fusion is a procedure of merging multiple images captured at unalike focus distances to produce a single composite image with improved sharpness and clarity. In this research, the purpose is to compare different popular frequency domain approaches for multi-focus image fusion, such as Discrete Wavelet Transforms (DWT), Stationary Wavelet Transforms (SWT), DCT-based Laplacian Pyramid (DCT-LP), Discrete Cosine Harmonic Wavelet Transform (DC-HWT), and Dual-Tree Complex Wavelet Transform (DT-CWT). The objective is to increase the understanding of these transformation techniques and how they can be utilized in conjunction with one another. The analysis will evaluate the 10 most crucial parameters and highlight the unique features of each method. The results will help determine which transformation technique is the best for multi-focus image fusion applications. Based on the visual and statistical analysis, it is suggested that the DCT-LP is the most appropriate technique, but the results also provide valuable insights into choosing the right approach.

제약적 최소 제곱 필터의 근사화를 이용한 실시간 방향 적응적 영상복원 (Approximated Constrained Least Squares Filter for Real-Time Directionally Adaptive Image Restoration)

  • 조창훈;전재환;백준기
    • 전자공학회논문지
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    • 제50권12호
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    • pp.150-158
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    • 2013
  • 본 논문에서는 절단된 제약적 최소 제곱 필터를 이용하여 방향 적응적으로 영상을 복원하는 방법을 제안한다. 제안하는 영상복원 필터는 공간영역에서 이론적으로 영상 전체의 크기를 갖는 제약적 최소 제곱(constrained least squares; CLS) 필터를 Maxwell-Boltzmann 커널을 사용하여 절단한 유한 임펄스 응답(finite impulse response; FIR) 필터의 구조로 실시간 영상복원을 가능하게 한다. 또한 화소 단위로 공분산 행렬을 분석하여 방향성을 추정하여, 화소마다 필터의 계수를 적응적으로 생성하여 방향 적응적으로 영상을 복원한다. 실험결과를 통해 기존의 알고리듬에 비해 제안된 방법이 선명하고 부작용(artifacts)이 적은 결과를 얻는 것을 검증하였다.

A Level Set Method to Image Segmentation Based on Local Direction Gradient

  • Peng, Yanjun;Ma, Yingran
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권4호
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    • pp.1760-1778
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    • 2018
  • For image segmentation with intensity inhomogeneity, many region-based level set methods have been proposed. Some of them however can't get the relatively ideal segmentation results under the severe intensity inhomogeneity and weak edges, and without use of the image gradient information. To improve that, we propose a new level set method combined with local direction gradient in this paper. Firstly, based on two assumptions on intensity inhomogeneity to images, the relationships between segmentation objects and image gradients to local minimum and maximum around a pixel are presented, from which a new pixel classification method based on weight of Euclidian distance is introduced. Secondly, to implement the model, variational level set method combined with image spatial neighborhood information is used, which enhances the anti-noise capacity of the proposed gradient information based model. Thirdly, a new diffusion process with an edge indicator function is incorporated into the level set function to classify the pixels in homogeneous regions of the same segmentation object, and also to make the proposed method more insensitive to initial contours and stable numerical implementation. To verify our proposed method, different testing images including synthetic images, magnetic resonance imaging (MRI) and real-world images are introduced. The image segmentation results demonstrate that our method can deal with the relatively severe intensity inhomogeneity and obtain the comparatively ideal segmentation results efficiently.