• Title/Summary/Keyword: Visual Signal

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A Digital Image Watermarking Using A Bottom-up Attention Module (상향식 주의 모듈을 사용한 디지털 워터마킹 기법)

  • Cheoi, Kyung-Joo
    • The KIPS Transactions:PartB
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    • v.15B no.4
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    • pp.293-300
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    • 2008
  • This paper takes a bottom-up attention module into consideration for digital image watermarking. A bottom-up attention module is employed to obtain the region of interest, and watermark information is embedded into the obtained region. Previous studies in digital image watermarking have been focused on the signal processing techniques, especially in waveform coding spreading watermarks over the entire target image. However, we notice that the third party's visual attention is usually concentrated on a few regions in an image but not on all of them. These regions are easy to be the target of attacks. If watermark information is inserted into these regions from the beginning, it can be detected with high correlation. Various kinds of images are tested, and the results showed good quality.

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.

Implement for EzPlay and PC-EPG of Multimedia Remote Control System (EzPlay/EPG를 적용한 멀티미디어 원격제어 시스템 구현)

  • Park Nho-Kyung;Jin Hun-Jun;Kim Sang-Pok;Park Sang-Bong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.42 no.2 s.302
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    • pp.39-48
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    • 2005
  • In this paper, we implement the multimedia remote control system by using existing internet service or wired online. We also provide user-friendly convenient environment with developed application program named EzPlay and PC-EPG. The multimedia remote control system consists of integrated wireless transceiver of PC and TV connected USB type and the users can easily use lots of contents because EzPlay program provides appropriate UI mode on the PC and TV screen. The unposed system can operate real-time playing, reserved video receding and data storing function using internet mesh based on signal detecting control theory. The PC-EPG system is implemented by server/client web program and the client program based on visual C++/MFC processes data storing in client computer through TCP/IP. It also provides intelligent function that constructs database according to user's preference.

A Video Summarization Study On Selecting-Out Topic-Irrelevant Shots Using N400 ERP Components in the Real-Time Video Watching (동영상 실시간 시청시 유발전위(ERP) N400 속성을 이용한 주제무관 쇼트 선별 자동영상요약 연구)

  • Kim, Yong Ho;Kim, Hyun Hee
    • Journal of Korea Multimedia Society
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    • v.20 no.8
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    • pp.1258-1270
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    • 2017
  • 'Semantic gap' has been a year-old problem in automatic video summarization, which refers to the gap between semantics implied in video summarization algorithms and what people actually infer from watching videos. Using the external EEG bio-feedback obtained from video watchers as a solution of this semantic gap problem has several another issues: First, how to define and measure noises against ERP waveforms as signals. Second, whether individual differences among subjects in terms of noise and SNR for conventional ERP studies using still images captured from videos are the same with those differently conceptualized and measured from videos. Third, whether individual differences of subjects by noise and SNR levels help to detect topic-irrelevant shots as signals which are not matched with subject's own semantic topical expectations (mis-match negativity at around 400m after stimulus on-sets). The result of repeated measures ANOVA test clearly shows a 2-way interaction effect between topic-relevance and noise level, implying that subjects of low noise level for video watching session are sensitive to topic-irrelevant visual shots, while showing another 3-way interaction among topic-relevance, noise and SNR levels, implying that subjects of high noise level are sensitive to topic-irrelevant visual shots only if they are of low SNR level.

Eyeball Movements Removal in EEG by Independent Component Analysis (독립성분분석에의한 뇌파 안구운동 제거)

  • Shim, Yong-Soo;Choi, Seong-Ho;Lee, Il-Keun
    • Annals of Clinical Neurophysiology
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    • v.3 no.1
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    • pp.26-30
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    • 2001
  • Purpose : Eyeball movement is one of the main artifacts in EEG. A new approach to the removal of these artifacts is presented using independent component analysis(ICA). This technique is a signal-processing algorithm to separate independent sources from unknown mixed signals. This study was performed to show that ICA is a useful method for the separation of EEG components with little data deformity. Methods : 12 sets of 10 sec digital EEG data including eye opening and closure were obtained using international 10~20 system scalp electrodes. ICA with 18 tracings of double banana bipolar montage was performed. Among obtained 18 independent components, two components, which were thought to be eyeball movements were removed. Other 16 components were reconstructed into original bipolar montage. Power spectral analysis of EEGs before and after ICA was done and compared statistically. Total 12 pairs of data were compared by visual inspection and relative power comparison. Results : Waveforms of each pair looked alike by visual inspection. Means of relative power before and after ICA were 29.16% vs. 28.27%, 12.12% vs. 12.41%, 10.55% vs. 10.52%, and 19.33% vs. 18. 33% for alpha, beta, theta, and delta, respectively. These values were statistically same before and after ICA. Conclusions : We found little data deformity after ICA and it was possible to isolate eyeball movements in EEG recordings. Many other components of EEG could be selectively separated using ICA.

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Study on Low Delay and Adaptive Video Transmission for a Surveillance System in Visual Sensor Networks (비디오 센서 망에서의 감시 체계를 위한 저지연/적응형 영상전송 기술 연구)

  • Lee, In-Woong;Kim, Hak-Sub;Oh, Tae-Geun;Lee, Sang-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.5
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    • pp.435-446
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    • 2014
  • Even if it is important to transmit high rate multimedia information without any transmission errors for surveillance systems, it is difficult to achieve error-free transmission due to infra-less adhoc networks. In order to reduce the transmission errors furthermore, additional signal overheads or retransmission of signals should be required, but they may lead to transmission delay. This paper represents a study on low delay and adaptive video transmission for the unmanned surveillance systems by developing system protocols. In addition, we introduce an efficient and adaptive control algorithm using system parameters for exploiting unmanned surveillance system properly over multi-channels.

Changes of Upper Trapezius Muscle Activity and EMG Gap After Transcutaneous Electrical Nerve Stimulation in Subjects With Myofascial Pain Syndrome (경피신경전기자극 후 상부 승모근 활성도와 EMG gap의 변화)

  • Koh, Eun-Kyung;Kwon, Oh-Yun;Yi, Chung-Hwi
    • Physical Therapy Korea
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    • v.10 no.1
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    • pp.37-50
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    • 2003
  • The purpose of this study was to compare visual analogue scale (VAS), pain threshold (PT), $%RMS_{RVC}$, and EMG gaps before and after applying transcutaneous electrical nerve stimulation (TENS) on the upper trapezius muscle at the patients with myofascial pain syndrome (MPS). The subjects were 4 men and 10 women composed of both the inpatients and outpatients who were diagnosed as MPS at Wonju Medical Center. VAS and PT measurements were performed to assess the subjective pain level. The reference voluntary contraction (RVC) test was performed for 15 seconds for normalization on the bilateral trapezius muscle using surface electromyography (sEMG). After 3-minute resting time, the EMG signal was recorded while performing a typing activity for 2 minutes and then TENS was applicated with a comfortable intensity for 10 minutes. The EMG activity of the upper trapezius muscle was recorded during typing for 2 minutes. The results of study were as follows: 1) VAS score was significantly decreased on the more painful side after treatment, however, it was not significantly different on the less painful side. 2) PT was increased after treatment on both sides, however, it was not significantly different between before and after the TENS application. 3) The EMG activity during typing was significantly decreased after treatment, and 4) The EMG gaps were significantly increased after TENS treatment compared to before it. Consequently, the study showed that TENS was effective in decreasing VAS, $%RMS_{RVC}$, and in increasing EMG gaps. The EMG gap analysis could be a useful method to measure pain in patients with MPS in the upper trapezius.

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Study on Vehicle Haptic-Seat for the Driving Information Transfer to Driver for the Elderly (고령운전자 운전정보전달을 위한 차량용 햅틱시트 연구)

  • Oh, S.Y.;Kim, K.T.;Yu, C.H.;Kwon, T.K.
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.8 no.3
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    • pp.151-160
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    • 2014
  • In this study, the effect of the automotive haptic-seat technology which can transmit the driving information by the vibro-stimulus from the seat was investigated to overcome previous system's limitation relied on the visual and audial method and to help handicap driving. A prototype haptic seat cover with 30 coin-type motors and driver module were developed for this sake. In an experiment of seat vibration stimulation being performed under virtual driving situation by targeting the elderly aged over 65 years old, average score of test subjects for total vibration recognition was 3.5/4 points and recognition rate of 87.5% was represented. In addition, a result that all the test subjects totally recognized overspeed warning signal of 4 times was represented. As a result of statistical analysis for vibration recognition score by each group depending on TMT score, a significant difference was not found and a result that tactile function of which vibration is recognized even by the aged whose visual, perceptional function is declined showed an equal ability was obtained.. In this study it was shown that the seat vibration stimulus could be used to transfer the old drivers' information while driving.

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Sequential Nonlinear Recurrence Quantification Analysis of Attentional Visual Evoked Potential (집중 시각자극 유발전위의 순차적 비선형 RQA 분석)

  • Lee, Byung-Chae;Yoo, Sun-Kook;Kim, Hye-Jin
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.11
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    • pp.195-205
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    • 2013
  • The analysis of electroencephalographic signal associated with the attention is essential for the understanding of human cognition. In this paper, the characteristic differences between the attention and inattention status in the brain were inspected by nonlinear analysis. The recurrence quantification analysis was applied to the relatively small number of samples of evoked potential having time varying characteristics, where the recurrence plot (RP), the color recurrence plot (CRP), and mean and time-sequential trend parameters were extracted. The dimension and the time delay in phase transformation can be determined by the paired set of extracted parameters. It is observed from RP, CRP, and parameters that the brain dynamics in attention is more complex than that in the inattention, as well as the synchronized brain response is stable in the mean sense but locally time varying. It is feasible that the non-linear analysis method can be useful for the analysis of complex brain dynamics associated during visual attentional task.

New developmental direction of telecommunications for Disabilities Welfare (장애인복지를 위한 정보통신의 발전방향)

  • 박민수
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.1
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    • pp.35-43
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    • 2000
  • This paper was studied on developmental direction of telecommunications for disabilities welfare. Method of this study is delphi method. Persons with disabilities is classed as motor disability, visual handicap, hearing impairment, and language and speech disorders. Persons with motor disability is needs as follow, speed recognition technology, video recognition technology, breath capacity recognition technology. Persons with visual handicap is needs as follow, display recognition technology, speed recognition technology, text recognition technology, intelligence conversion handling technology, video recognition - speed synthetic technology. Persons with hearing impairment and language - speech disorders is needs as follow, speed signal handling technology, speed recognition technology, intelligence conversion handling technology, video recognition technology, speed synthetic technology the results of this study is as follow: first, disabilities telecommunications organization must be constructed. Second, persons with disabilities in need of universal service. Third, Persons with disabilities in need of information education, Fourth, studying for telecommunications in need of support. Fifth, small telecommunications company in need of support. Sixth, software industry in need of new development. Seventh, Persons with disabilities in need of standard guideline for telecommunications.

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