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Blind Watermarking Scheme Using Singular Vectors Based on DWT/RDWT/SVD

  • Luong, Ngoc Thuy Dung;Sohn, Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2015.11a
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    • pp.173-175
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    • 2015
  • We proposed a blind watermarking scheme using singular vectors based on Discrete Wavelet Transform (DWT) and Redundant Discrete Wavelet Transform (RDWT) combined with Singular Value Decomposition (SVD) for copyright protection application. We replaced the 1st left and right singular vectors decomposed from cover image with the corresponding ones from watermark image to overcome the false-positive problem in current watermark systems using SVD. The proposed scheme realizes the watermarking system without a false positive problem, and shows high fidelity and robustness.

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Improved Reliable SVD-Based Watermark Scheme For Ownership Verification (소유권 확인을 위한 향상된 고신뢰성 SVD 기반 워터마킹기법)

  • Luong, Ngoc Thuy Dung;Sohn, Won
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2016.11a
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    • pp.82-84
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    • 2016
  • We propose a new reliable SVD-based watermarking scheme having high fidelity and strong robustness with no false-positive problem. Each column of the principal component of a watermark image is embedded into singular values of LL, LH, HL and HH sub-bands of cover image with different scale factors. Each scale factor is optimized by trading-off fidelity and robustness using Differential Evolution (DE) algorithm. The proposed scheme improves fidelity and robustness of existing reliable SVD based watermarking schemes without any false-positive problem. Index Terms - watermarking, reliable SVD, DWT, principal component, Differential Evolution.

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A Study on the Image Steganographic method using Multi-pixel Differencing and LSB Substitution Methods (다중 픽셀 차이값과 LSB 교체 기법을 이용한 이미지 스테가노그래픽 기법 연구)

  • Ha, Kyeoung-Ju;Jung, Ki-Hyun;Yoo, Kee-Young
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.3
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    • pp.23-30
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    • 2008
  • A data hiding method based on least significant bit (LSB) substitution and multi-pixel differencing (MPD) is presented on the proposed method to improve the capacity of the hidden secret data and to provide an imperceptible visual quality. First, a sum of different values for four-pixel sub-block is calculated. The low value of the sum can be located on a smooth block and the high value is located on an edged block. The secret data are hidden into the cover image by LSB method in the smooth block, while MPD method in the edged block. The experimental results show that the proposed method has a higher capacity and maintains a good visual quality.

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Detecting Steganographic Contents Using EWM Statistics (EWM 통계량을 이용한 스테가노그래픽 자료 감지 기법)

  • Ji, Seon-Su
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.3
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    • pp.54-62
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    • 2008
  • For a message hiding technique to be effectual, it needs to have availability, confidentiality and integrity. Steganography is the science of hiding one message within other types of digital contents. In this case, attempt to defeat steganalysis by restoring the statistics of the composite image to resemble that of the cover, these discrepancies expose the fact that hidden communication is happening. In this paper, I present a steganography scheme capable of concealing a piece of secrete information in a host image and base on the technique's OCT, RGB, statistical restoration.

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An Assessment of Urbanization Using Historic Satellite Photography: Columbus Metropolitan Area, Ohio, 1965

  • Kim, Kee-Tae;Kim, Jung-Hwan;Jayakumar, S.;Sohn, Hong-Gyoo
    • Korean Journal of Remote Sensing
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    • v.23 no.3
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    • pp.221-227
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    • 2007
  • We present an analysis of urban development and growth with reconnaissance satellite photographs of Columbus metropolitan area acquired by the Corona program in 1965. A two-dimensional polynomial linear transformation was used to rectify the photos against United State Geological Survey (USGS) Large-scale Digital Line Graph (DLG) data georeferenced to Universal Transverse Mercator (UTM) coordinates. The boundaries of the Columbus metropolitan area were extracted from the rectified Corona image mosaic using a Bayesian approach to image segmentation. The inferred 1965 urban boundaries were compared with 1976 USGS Land Use and Land Cover (LULC) data and boundaries derived from 1988 and 1994 Landsat TM images. The urban area in and around Columbus approximately doubled from 1965 to 1994 (${\sim}110%$) along with population growth from 1960 to 1998 (${\sim}50%$). Most of the urban expansion results from development of residential units.

Virtual Viewpoint Image Synthesis Algorithm using Multi-view Geometry (다시점 카메라 모델의 기하학적 특성을 이용한 가상시점 영상 생성 기법)

  • Kim, Tae-June;Chang, Eun-Young;Hur, Nam-Ho;Kim, Jin-Woong;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12C
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    • pp.1154-1166
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    • 2009
  • In this paper, we propose algorithms for generating high quality virtual intermediate views on the baseline or out of baseline. In this proposed algorithm, depth information as well as 3D warping technique is used to generate the virtual views. The coordinate of real 3D image is calculated from the depth information and geometrical characteristics of camera and the calculated 3D coordinate is projected to the 2D plane at arbitrary camera position and results in 2D virtual view image. Through the experiments, we could show that the generated virtual view image on the baseline by the proposed algorithm has better PSNR at least by 0.5dB and we also could cover the occluded regions more efficiently for the generated virtual view image out of baseline by the proposed algorithm.

A Semi-fragile Image Watermarking Scheme Exploiting BTC Quantization Data

  • Zhao, Dongning;Xie, Weixin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.4
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    • pp.1499-1513
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    • 2014
  • This paper proposes a novel blind image watermarking scheme exploiting Block Truncation Coding (BTC). Most of existing BTC-based watermarking or data hiding methods embed information in BTC compressed images by modifying the BTC encoding stage or BTC-compressed data, resulting in watermarked images with bad quality. Other than existing BTC-based watermarking schemes, our scheme does not really perform the BTC compression on images during the embedding process but uses the parity of BTC quantization data to guide the watermark embedding and extraction processes. In our scheme, we use a binary image as the original watermark. During the embedding process, the original cover image is first partitioned into non-overlapping $4{\times}4$ blocks. Then, BTC is performed on each block to obtain its BTC quantized high mean and low mean. According to the parity of high mean and the parity of low mean, two watermark bits are embedded in each block by modifying the pixel values in the block to make sure that the parity of high mean and the parity of low mean in the modified block are equal to the two watermark bits. During the extraction process, BTC is first performed on each block to obtain its high mean and low mean. By checking the parity of high mean and the parity of low mean, we can extract the two watermark bits in each block. The experimental results show that the proposed watermarking method is fragile to most image processing operations and various kinds of attacks while preserving the invisibility very well, thus the proposed scheme can be used for image authentication.

Make-up culture and Image of Korean Women in the late 20th Century (20세기 후반 한국 여성의 화장 문화와 화장 이미지 연구)

  • Kim, Min-Je;Park, Hye-Won
    • Journal of Fashion Business
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    • v.15 no.4
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    • pp.67-86
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    • 2011
  • This study intended to understand overall history of make-up in Korea in an integrated and diachronic context by interpreting women's will and desire to express themselves reflected in the cosmetics culture in each period centering on women's magazine cover, cosmetics advertisement, and articles from 1950 to 1999 and examining women's make-up image and characteristics in each period. A total of 919 women's magazines (Yeonwon (Women's Garden), Woman Sense, Yeoseong Donga (Women's Donga), Jubusaenghwal (Homemaker's Living), Yeoseong Jungang (Women's Jungang)) issued between 1950 and 1999 were examined for the study. Key words of each period were extracted through fashion and beauty related articles and advertisement titles to examine the make-up culture of Korean women and set the standard for the make-up image of Korean women. A total 1,252 pictures were shot for each period and categorized based on the standard for the make-up image of Korean women. Then, the changes in the make-up image of Korean women were examined and identified the characteristics of images along with the change of images in each period. Next, the meaning of each make-up image was examined. This can be interpreted as the expression of values and desire by modern Korean women, especially Korean women in the late 20th century, as well as the consciousness for coping with the changing society.

Feature Selection for Image Classification of Hyperion Data (Hyperion 영상의 분류를 위한 밴드 추출)

  • 한동엽;조영욱;김용일;이용웅
    • Korean Journal of Remote Sensing
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    • v.19 no.2
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    • pp.170-179
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    • 2003
  • In order to classify Land Use/Land Cover using multispectral images, we have to give consequence to defining proper classes and selecting training sample with higher class separability. The process of satellite hyperspectral image which has a lot of bands is difficult and time-consuming. Furthermore, classification result of hyperspectral image with noise is often worse than that of a multispectral image. When selecting training fields according to the signatures in the study area, it is difficult to calculate covariance matrix in some clusters with pixels less than the number of bands. Therefore in this paper we presented an overview of feature extraction methods for classification of Hyperion data and examined effectiveness of feature extraction through the accuracy assesment of classified image. Also we evaluated the classification accuracy of optimal meaningful features by class separation distance, which is also a method for band reduction. As a result, the classification accuracies of feature-extracted image and original image are similar regardless of classifiers. But the number of bands used and computing time were reduced. The classifiers such as MLC, SAM and ECHO were used.

Analyzing Image Quality and Disinfection Effectiveness of Alcohol Gel Application in Ultrasound Scans (초음파 스캔에서 알코올 겔 적용 시 화질과 소독효과 분석)

  • Hyeon-Ju Kim
    • Journal of the Korean Society of Radiology
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    • v.18 no.4
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    • pp.365-372
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    • 2024
  • To analyze the image quality and disinfection effectiveness of alcohol gel application in ultrasound scans, we varied the application of alcohol gels with different alcohol content from ultrasound gels. The image quality analysis compared the Dead zone, axial and lateral resolution, sensitivity, and gray scale changes using the ATS-539 phantom, while the disinfection effectiveness analysis was performed by swabbing the three cover faces of convex probe used in clinical practice, collecting specimens and enrichment culture them for 24 hours before identification with Gram stain. image quality analysis showed that all items, regardless of the alcohol content, produced images that were not different from the ultrasonic gel application images, and pathogens such as staphylococcus aureus, streptococcus, and enterococcus were detected on all probes, and all were extinction by the application of alcohol gel. The application of alcohol gel during ultrasound examination was meaningful in terms of image quality maintenance and disinfection effect, and if the results of this study are further studied and commercialized, the application of alcohol gel as an alternative to ultrasound gel will be very useful in clinical examinations because it can consider not only image quality but also infection prevention.