• Title/Summary/Keyword: 가역실험

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Interval-based Audio Integrity Authentication Algorithm using Reversible Watermarking (가역 워터마킹을 이용한 구간 단위 오디오 무결성 인증 알고리즘)

  • Yeo, Dong-Gyu;Lee, Hae-Yeoun
    • The KIPS Transactions:PartB
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    • v.19B no.1
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    • pp.9-18
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    • 2012
  • Many audio watermarking researches which have been adapted to authenticate contents can not recover the original media after watermark removal. Therefore, reversible watermarking can be regarded as an effective method to ensure the integrity of audio data in the applications requiring high-confidential audio contents. Reversible watermarking inserts watermark into digital media in such a way that perceptual transparency is preserved, which enables the restoration of the original media from the watermarked one without any loss of media quality. This paper presents a new interval-based audio integrity authentication algorithm which can detect malicious tampering. To provide complete reversibility, we used differential histogram-based reversible watermarking. To authenticate audio in parts, not the entire audio at once, the proposed algorithm processes audio by dividing into intervals and the confirmation of the authentication is carried out in each interval. Through experiments using multiple kinds of test data, we prove that the presented algorithm provides over 99% authenticating rate, complete reversibility, and higher perceptual quality, while maintaining the induced-distortion low.

Reversible Image Watermarking with Differential Histogram Shifting and Error Prediction Compensation (차이값 히스토그램 쉬프팅과 오류 예측 보정을 이용한 가역 영상 워터마킹)

  • Yeo, Dong-Gyu;Lee, Hae-Yeoun;Kim, Byeong-Man;Kim, Kyung-Su
    • Journal of KIISE:Software and Applications
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    • v.37 no.6
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    • pp.417-429
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    • 2010
  • Reversible watermarking inserts watermark into digital media in such a way that visual transparency is preserved and then enables to restore the original media from the marked one without any loss of media quality. This watermarking can be applied to quality-sensitive imaging such as medical imaging, military imaging, remote-sensing imaging, and precious artwork, where the original media should be preserved during image processing and analysis. In this paper, a reversible image watermarking technique that embeds message bits by modifying the differential histogram of adjacent pixels is presented. In order to satisfy both high embedding capacity and visual quality, the proposed technique exploits the fact that adjacent pixels in the image have highly spatial correlation. Also, we prevent overflow/underflow problem and salt-and-pepper artifacts by employing a predicted error compensation scheme. Through experiments using various test images, we prove that the presented technique provides perfect reversibility and high embedding capacity, while maintaining the induced-distortion low.

Block-based Image Authentication Algorithm using Differential Histogram-based Reversible Watermarking (차이값 히스토그램 기반 가역 워터마킹을 이용한 블록 단위 영상 인증 알고리즘)

  • Yeo, Dong-Gyu;Lee, Hae-Yeoun
    • The KIPS Transactions:PartB
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    • v.18B no.6
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    • pp.355-364
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    • 2011
  • In most applications requiring high-confidential images, reversible watermarking is an effective way to ensure the integrity of images. Many watermarking researches which have been adapted to authenticate contents cannot recover the original image after authentication. However, reversible watermarking inserts the watermark signal into digital contents in such a way that the original contents can be restored without any quality loss while preserving visual quality. To detect malicious tampering, this paper presents a new block-based image authentication algorithm using differential histogram-based reversible watermarking. To generate an authentication code, the DCT-based authentication feature from each image block is extracted and combined with user-specific code. Then, the authentication code is embedded into image itself with reversible watermarking. The image can be authenticated by comparing the extracted code and the newly generated code and restored into the original image. Through experiments using multiple images, we prove that the presented algorithm has achieved over 97% authentication rate with high visual quality and complete reversibility.

Effects of nicotine on the attachment and proliferation of periodontal ligament cells, and reversibility of nicotine-induced cytotoxicity (니코틴이 치주인대세포의 부착과 증식에 미치는 영향 및 니코틴에 의해 야기된 세포독성의 가역성에 대한 연구)

  • Kim, Hye-Kyung;Park, Jin-Woo;Choi, Byung-Ju;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.35 no.2
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    • pp.475-490
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    • 2005
  • 본 실험은 흡연이 치주인대세포의 기능에 미치는 영향을 알아보기 위해 담배 부산물 중 하나인 니코틴이 지주인대세포의 부착과 성장 및 세포의 가역성에 미치는 영향을 관찰하였다. 니코틴이 치주인대세포의 부착에 미치는 영향을 관찰하기 위하여 치주인대세포에 니코틴을 투여한 후 1, 3, 6, 12, 24시간째 trypan blue 염색 후 부착된 세포수의 측정과 H&E stain후 형태학적 관찰을 하였고 니코틴이 치주인대세포의 성장에 미치는 영향을 관찰하기 위하여 치주인대세포에 니코틴을 투여한 후 1, 4, 7, 11, 14일째 trypan blue 염색 후 증식된 세포수의 측정과 H&E stain후 형태학적 관찰을 하였다. 또 니코틴의 세포독성효과의 가역성 평가를 위하여 니코틴을 투여하고 1, 4, 7, 11일째 니코틴이 없는 새로운 배지로 갈아주어 2일 더 배양한 후 trypan blue로 염색하여 세포수를 측정, 비교하였고 H&E 염색 후 형태학적 관찰을 하였다. 실험결과 니코틴 농도가 증가함에 따라 치주인대세포의 부착율은 감소되었고 24시간 배양 후 2mg/ml, 0.5mg/ml, 0.1mg/ml니코틴 투여군에서 통계학적으로 유의성 있는 부착억제가 관찰되었고(P<0.01) 형태학적 관찰결과 2mg/ml, 0.5mg/ml 니코틴 투여군에서는 대조해서 관찰되는 세포질의 확장이 관찰되지 않았다. 니코틴이 치주인대세포의 증식에 미치는 효과를 살펴본 결과 2mg/ml, 0.5mg/ml, 0.1mg/ml 니코틴 투여군에서 증식억제가 관찰되었고(P<0.01) 0.005mg/ml이하의 니코틴 투여군에서는 아무런 변화도 관찰되지 않았다. 14일 배양 후 형태학적 관찰결과 0.1mg/ml 니코틴 투여군에서 세포질내 공포를 관찰할 수 있었고 2mg/ml, 0.5mg/ml 니코틴 투여군에서는 세포의 괴사가 나타났다. 니코틴의 세포독성효과의 가역성평가결과 2mg/ml이상의 니코틴은 세포에 비가역적인 손상을 일으키며 0.5mg/ml, 0.1mg/ml 니코틴에 의한 세포독성은 초기에는 가역적이나 장기간 세포에 노출시키면 비가역적인 손상을 야기하는 것으로 나타났다.(P<0.05) 본 실험결과 담배의 구성성분 중 니코틴은 농도 의존적으로 치주인대세포의 부착과 증식에 영향을 주었고 니코틴의 치주인대세포에 대한 독성효과는 농도가 증가할수록, 시간이 지닐수록 비가역적으로 나타났다. 따라서 흡연은 치주조직재생에 영향을 미칠 것으로 생각되며 흡연의 기간과 정도가 치주질환의 심도 및 치주치료 후 불량한 치유반응과 관계가 있을 것으로 사료된다.

Reversible Watermarking based Video Contents Management and Control technique using Biological Organism Model (생물학적 유기체 모델을 이용한 가역 워터마킹 기반 비디오 콘텐츠 관리 및 제어 기법)

  • Jang, Bong-Joo;Lee, Suk-Hwan;Kwon, Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.16 no.7
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    • pp.841-851
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    • 2013
  • The infectious information hiding system(IIHS) is proposed for secure distribution of high quality video contents by applying optimized watermark embedding and detection algorithms to video codecs. And the watermark as infectious information is transmitted while target video is displayed or edited by codecs. This paper proposes a fast and effective reversible watermarking and infectious information generation for IIHS. Our reversible watermarking scheme enables video decoder to control video quality and watermark strength actively for by adding control code and expiration date with the watermark. Also, we designed our scheme with low computational complexity to satisfy it's real-time processing in a video codec, and to prevent time or frame delay during watermark detection and video restoration, we embedded one watermark and one side information within a macro-block. Experimental results verify that our scheme satisfy real-time watermark embedding and detection and watermark error is 0% after reversible watermark detection. Finally, we conform that the quality of restored video contens is almost same with compressed video without watermarking algorithm.

Performance analysis on modified integer transforms for lossless image compression (무손실 영상 압축을 위한 변형된 정수 변환들에 대한 성능 분석)

  • Kim, Hui-Gyeong;Yoo, Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.6
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    • pp.1273-1278
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    • 2012
  • In this paper, we introduce modified integer transforms for lossless image compression and evaluate their performances for two-dimensional transforms. The two-dimensional extensions of the modified integer transforms show different performances in terms of coding efficiency and computational complexity. Thus, we measure performances for two-dimensional separable transforms and a two-dimensional non-separable transform. The separable modified integer transform used in H.264, the modified integer transform using the lifting scheme, and the non-separable transform in JPEG XR are evaluated in this paper. Also, experiments and their results are given. The experimental results indicate that the modified integer transform using the lifting scheme shows the best performance in terms of compression efficiency.

Reversible Data Embedding Algorithm Using the Locality of Image and the Adjacent Pixel Difference Sequence (영상의 지역성과 인접 픽셀 차분 시퀀스를 이용하는 가역 데이터 임베딩 기법)

  • Jung, Soo-Mok
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.6
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    • pp.573-577
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    • 2016
  • In this paper, reversible data embedding scheme was proposed using the locality of image and the adjacent pixel difference sequence. Generally, locality exists in natural image. The proposed scheme increases the amount of embedding data and enables data embedding at various levels by applying a technique of predicting adjacent pixel values using image locality to an existing technique APD(Adjacent Pixel Difference). The experimental results show that the proposed scheme is very useful for reversible data embedding.

An Efficient Reversible Data Hiding Algorithm (효율적인 가역 데이터 은닉 기법)

  • Jung, Soo-Mok
    • Journal of Service Research and Studies
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    • v.6 no.1
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    • pp.71-81
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    • 2016
  • An efficient reversible data hiding algorithm was proposed in this paper. The original image can be recovered from the stego-image without distortion during the embedded data are extracted from the stego-image. The embedding data are greater than that of the previous algorithm and the PSNR value of the stego-image is guaranteed to be greater than 48dB. The performance of the proposed algorithm was proved by experimental results.

Degradation Evaluation of Mechanical Properties for 12Cr Ferrite Heat Resisting Steel by Reversible Permeability (가역투자율에 의한 12Cr 페라이트 내열강의 역학적 물성의 열화평가)

  • Ryu, Kwon-Sang;Kim, Min-Gi;Nahm, Seung-Hoon;Kim, Chung-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.30 no.5
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    • pp.464-470
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    • 2010
  • The integrity of the industrial equipment in use under high temperature and high pressure must be assessed by regularly measuring the degraded mechanical properties during service time. In order to nondestructively monitor the degraded mechanical properties of industrial equipment, a measuring method of the reversible permeability(RP) using surface type probe is presented. The method for measuring the RP is based on that RP is the differential value of hysteresis loop. The RP is exactly the foundation hatmonics induced in a detecting coil measured by lock-in amplifier tuned to a frequency of the alternating perturbing magnetic field. The peak of RP is measured around the coercive force. Steel material used in this work was 12Cr ferritic heat resisting steel. The eleven kinds of samples aged during different times under same temperature ($700^{\circ}C$) were prepared. Peak interval of reversible permeability(PIRP), Vickers hardness, and tensile strength measured for the aged samples decreased abruptly for short aging time (below 500 h), but the change became small at a long aging time. Vickers hardness and tensile strength linearly decreased as RIRP decreased, so the degraded mechanical properties of 12Cr ferritic heat resisting steel could be nondestructively evaluated by measuring RIRP.