• Title/Summary/Keyword: sub-image

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Image Retrieval via Query-by-Layout Using MPEG-7 Visual Descriptors

  • Kim, Sung-Min;Park, Soo-Jun;Won, Chee-Sun
    • ETRI Journal
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    • v.29 no.2
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    • pp.246-248
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    • 2007
  • Query-by-example (QBE) is a well-known method for image retrieval. In reality, however, an example image to be used for the query is rarely available. Therefore, it is often necessary to find a good example image to be used for the query before applying the QBE method. Query-by-layout (QBL) is our proposal for that purpose. In particular, we make use of the visual descriptors such as the edge histogram descriptor (EHD) and the color layout descriptor (CLD) in MPEG-7. Since image features of the CLD and the EHD can be localized in terms of a$4{\times}4$ sub-image, we can specify image features such as color and edge distribution on each sub-image separately for image retrieval without a query image. Experimental results show that the proposed query method can be used to retrieve a good image as a starting point for further QBE-based image retrieval.

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H Control on the Optical Image Stabilizer Mechanism in Mobile Phone Cameras (이동통신 단말기 카메라의 손떨림 보정 장치의 H 제어)

  • Lee, Chibum
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.3
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    • pp.266-272
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    • 2014
  • This study proposes a closed-loop shaping control method with $H_{\infty}$ optimization for optical image stabilization (OIS) in mobile phone cameras. The image stabilizer is composed of a horizontal stage constrained by ball bearings and actuated by the magnetic force from voice coil motors. The displacement of the stage is measured by Hall effect sensors. From the OIS frequency response experiment, the transfer function models of the stage and Hall effect sensor were identified. The weight functions were determined considering the tracking performance, noise attenuation, and stability with considerable margins. The $H_{\infty}$ optimal controller was executed using closed-loop shaping and limiting the controller order, which should be less than 6 for real-time implementation. The control algorithm was verified experimentally and proved to operate as designed.

Sub-Pixel Analysis of Hyperspectral Image Using Linear Spectral Mixing Model and Convex Geometry Concept

  • Kim, Dae-Sung;Kim, Yong-Il;Lim, Young-Jae
    • Korean Journal of Geomatics
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    • v.4 no.1
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    • pp.1-8
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    • 2004
  • In the middle-resolution remote sensing, the Ground Sampled Distance (GSD) that the detector senses and samples is generally larger than the actual size of the objects (or materials) of interest, and so several objects are embedded in a single pixel. In this case, as it is impossible to detect these objects by the conventional spatial-based image processing techniques, it has to be carried out at sub-pixel level through spectral properties. In this paper, we explain the sub-pixel analysis algorithm, also known as the Linear Spectral Mixing (LSM) model, which has been experimented using the Hyperion data. To find Endmembers used as the prior knowledge for LSM model, we applied the concept of the convex geometry on the two-dimensional scatter plot. The Atmospheric Correction and Minimum Noise Fraction techniques are presented for the pre-processing of Hyperion data. As LSM model is the simplest approach in sub-pixel analysis, the results of our experiment is not good. But we intend to say that the sub-pixel analysis shows much more information in comparison with the image classification.

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Comprehensive study of components affecting extrinsic transconductance in In0.7Ga0.3As quantum-well high-electron-mobility transistors for image sensor applications (이미지 센서 적용을 위한 In0.7Ga0.3As QW HEMT 소자의 extrinsic trans-conductance에 영향을 미치는 성분들의 포괄적 연구)

  • Yun, Seung-Won;Kim, Dae-Hyun
    • Journal of Sensor Science and Technology
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    • v.30 no.6
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    • pp.441-445
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    • 2021
  • The components affecting the extrinsic transconductance (gm_ext) in In0.7Ga0.3As quantum-well (QW) high-electron-mobility transistors (HEMTs) on an InP substrate were investigated. First, comprehensive modeling, which only requires physical parameters, was used to explain both the intrinsic transconductance (gm_int) and the gm_ext of the devices. Two types of In0.7Ga0.3As QW HEMT were fabricated with gate lengths ranging from 10 ㎛ to sub-100 nm. These measured results were correlated with the modeling to describe the device behavior using analytical expressions. To study the effects of the components affecting gm_int, the proposed approach was extended to projection by changing the values of physical parameters, such as series resistances (RS and RD), apparent mobility (𝜇n_app), and saturation velocity (𝜈sat).

Reversible Sub-Feature Retrieval: Toward Robust Coverless Image Steganography for Geometric Attacks Resistance

  • Liu, Qiang;Xiang, Xuyu;Qin, Jiaohua;Tan, Yun;Zhang, Qin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.3
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    • pp.1078-1099
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    • 2021
  • Traditional image steganography hides secret information by embedding, which inevitably leaves modification traces and is easy to be detected by steganography analysis tools. Since coverless steganography can effectively resist steganalysis, it has become a hotspot in information hiding research recently. Most coverless image steganography (CIS) methods are based on mapping rules, which not only exposes the vulnerability to geometric attacks, but also are less secure due to the revelation of mapping rules. To address the above issues, we introduced camouflage images for steganography instead of directly sending stego-image, which further improves the security performance and information hiding ability of steganography scheme. In particular, based on the different sub-features of stego-image and potential camouflage images, we try to find a larger similarity between them so as to achieve the reversible steganography. Specifically, based on the existing CIS mapping algorithm, we first can establish the correlation between stego-image and secret information and then transmit the camouflage images, which are obtained by reversible sub-feature retrieval algorithm. The received camouflage image can be used to reverse retrieve the stego-image in a public image database. Finally, we can use the same mapping rules to restore secret information. Extensive experimental results demonstrate the better robustness and security of the proposed approach in comparison to state-of-art CIS methods, especially in the robustness of geometric attacks.

Accelerated compression of sub-images by use of effective motion estimation and difference image methods in integral imaging (집적영상에서 효율적인 물체움직임 추정 및 차 영상 기법을 이용한 서브영상의 고속 압축)

  • Lee, Hyoung-Woo;Kim, Eun-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.12
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    • pp.2762-2770
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    • 2012
  • In this paper, we propose a novel approach to effectively compress the sub-images transformed from the picked-up elemental images in integral imaging, in which motion vectors of the object in each sub-image are fast and accurately estimated and compensated by combined use of MSE(mean square error)-based TSS(tree-step search) and FS(full search) schemes. This is, the possible object areas in each sub-image are searched by using the fast TSS algorithm in advance, then the these selected object areas are fully searched with the accurate FS algorithm. Furthermore, the sub-images in which all object's motion vectors are compensated, are transformed into the residual images by using the difference image method and finally compressed with the MPEG-4 algorithm. Experimental results reveal that the proposed method shows 214% improvement in the compression time per each image frame compared to that of the conventional method while keeping the same compression ratio with the conventional method. These successful results confirm the feasibility of the proposed method in the practical application.

An Analysis of Previous Researches on Clothing Image and Make-up Image (의복이미지와 화장이미지에 관한 기존 연구 분석)

  • Lee Hyun-Jung;Kim Mi-Young
    • Journal of the Korean Society of Costume
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    • v.54 no.7
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    • pp.91-106
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    • 2004
  • The purpose of this study was to review the previous researches, analyze the clothing image, the make-up image and compare the analyses of clothing image and make-up image. The previous researches of clothing image and make-up image were reviewed in 6 kinds of Journal. The results of previous research review and analysis were followed as : Measuring mean of image are used to similarly that semantic differential technique and summated rating technique. Attention to proposed researcher abstraction image in make-up image, but there is problem that this hard to explain objectivity of image abstraction. There are a lot of occasions that 4 or 5 image factors were extracted by factor analysis. The make-up image researches that presented image stimulus were more than study that do not present. Image words were classified which were compiled words have similar sub image. Grace, activeness, lively. unique, modernity attractive, feminine. sexy and ripeness clothing images were classified factors. which were representative clothing image. Elegance, Sophisticate. romantic, natural, modern and youthfulness make-up image for factor were representative make-up image factors. However the problems were found that some representative image factor included the sub images which were different from some factor image. Compared with representation image words, same image words were used to not agree what clothing image and make-up image. Standardization of word should be made that show that clothing image and make-up image.

Image Denoising using Adaptive Threshold Method in Wavelet Domain

  • Gao, Yinyu;Kim, Nam-Ho
    • Journal of information and communication convergence engineering
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    • v.9 no.6
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    • pp.763-768
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    • 2011
  • Image denoising is a lively research field. Today the researches are focus on the wavelet domain especially using wavelet threshold method. We proposed an adaptive threshold method which considering the characteristic of different sub-band, the method is adaptive to each sub-band. Experiment results show that the proposed method extracts white Gaussian noise from original signals in each step scale and eliminates the noise effectively. In addition, the method also preserves the detail information of the original image, obtaining superior quality image with higher peak signal to noise ratio(PSNR).

CERTAIN IMAGE FORMULAS OF (p, 𝜈)-EXTENDED GAUSS' HYPERGEOMETRIC FUNCTION AND RELATED JACOBI TRANSFORMS

  • Chopra, Purnima;Gupta, Mamta;Modi, Kanak
    • Communications of the Korean Mathematical Society
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    • v.37 no.4
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    • pp.1055-1072
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    • 2022
  • Our aim is to establish certain image formulas of the (p, 𝜈)-extended Gauss' hypergeometric function Fp,𝜈(a, b; c; z) by using Saigo's hypergeometric fractional calculus (integral and differential) operators. Corresponding assertions for the classical Riemann-Liouville(R-L) and Erdélyi-Kober(E-K) fractional integral and differential operators are deduced. All the results are represented in terms of the Hadamard product of the (p, 𝜈)-extended Gauss's hypergeometric function Fp,𝜈(a, b; c; z) and Fox-Wright function rΨs(z). We also established Jacobi and its particular assertions for the Gegenbauer and Legendre transforms of the (p, 𝜈)-extended Gauss' hypergeometric function Fp,𝜈(a, b; c; z).

Effect of Mg Additive in the Bi1.84Pb0.34Sr1.91Ca2.03Cu3.06O10+δ(110 K phase) Superconductors (Bi1.84Pb0.34Sr1.91Ca2.03Cu3.06O10+δ(110 K 상)산화물 고온초전도체에 Mg 첨가에 따른 영향)

  • 이민수
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.6
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    • pp.522-531
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    • 2003
  • Samples with the nominal composition, B $i_{1.84}$P $b_{0.34}$S $r_{1.91}$C $a_{2.03}$C $u_{3.06}$ $O_{10+{\delta}}$ high- $T_{c}$ superconductors containing MgO as an additive were fabricated by a solid-state reaction method. Samples with MgO of 5~30 wt% each were sintered at 820~86$0^{\circ}C$ for 24 hours. The structural characteristics, critical temperature, grain size and image of mapping with respect to MgO contents were analyzed by XRD(X-Ray Diffraction), SEM(Scanning Electron Microscope) and EDS(Energy dispersive X-ray spectrometer) respectively. As MgO contents increased, intensity of MgO Peaks and ratio of Bi-2212 phase in superconductors intensified and the proportion of the phase transition from Bi-2223 to Bi-2212 was increased.