• 제목/요약/키워드: Video-conference

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DRM 기반 MP4 스트리밍을 위한 비디오 암호화 알고리즘에 관한 연구 (A Study on Video Encryption Algorithm for DRM-based MP4 Streaming)

  • 김정현;윤기송;전경표
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2003년도 춘계종합학술대회논문집
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    • pp.218-222
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    • 2003
  • Internet의 발달로 사람들은 정보를 쉽게 얻을 수 있을 뿐만 아니라 교환하고 유통할 수 있게 됨에 따라 컨텐츠 불법복제 문제를 야기 시키고 이로 인해 저작권 보호에 대한 관심이 높아지고 있다. VOD(Video On Demand)와 인터넷 방송과 같은 멀티미디어 상거래 또한 사용 권리를 가진 사용자만이 컨텐츠에 접근하고 이용할 수 있어야 한다. 본 논문에서는 MP4 기반 스트리밍 서비스 모델에 적용할 수 있는 DRM(Digital Rights Management) 시스템을 제시하여 이 DRM 시스템에 적용할 수 있는 MP4 암호화 알고리즘을 제안한다.

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재가노인생활지원기기의 실용화를 위한 여성노인의 선호 연구 (A Study on the Preference of Feminine Seniors for the Higher Usability of Life Support Appliances)

  • 김선중;박경옥
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 2008년 추계학술발표대회 논문집
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    • pp.407-412
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    • 2008
  • The purpose of this study is to find out the preference and the opinion of feminine seniors on the life support appliances(video phone, medication dispenser, activity monitor and sleep monitor). The appliances may be improved reflecting the result of the preferred functions and designs. The respondents were 141 feminine seniors of 65 years & older, living in Ulsan city or Cheongju city, Korea. Following is the result. 1) All the responses answered that the medication dispenser, video phone and activity monitor, sleep monitor are useful appliances. 2) All the seniors expressed prefer to function of the appliances, and were highly concerned about the price, safety and convenience. 3)The preferred designs were (1) white or red standing medication dispenser,(2) wall-mounted video phone working by voice, (3) metal activity monitor sensor like white or yellow bracelet.

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객관적 영상 화질 평가 기준를 위한 움직임 정보에 따른 중요도 결정 기법 (Weighting Method based on Motion Information for Objective Video Quality Assessment)

  • 박수영;김태완;이상훈
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.909-910
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    • 2008
  • For evaluating the performance of some codecs, many researchers have study and develop new objective video quality assessments. However, it's not sufficient for evaluating the temporal feature of video data yet, which is a distinguishable and representative characteristic when compared with other multimedia. This paper propose the method to apply the weight to SSIM (Structural SIMilarity) according to the cognitive psychological feature. And, we presented that the performance of objective video quality assessment applied the weight to SSIM by using the proposed method is superior to one of original SSIM.

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스케일러블 비디오 부호화와 AT-DMB (Scalable Video Coding and its Application to AT-DMB)

  • 김재곤;김진수;최해철;강정원
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.45-48
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    • 2008
  • This paper presents a brief overview of scalable video coding (SVC) with a focus on spatial scalability and its application to Advanced Terrestrial-DMB (AT-DMB). By adopting SVC with two spatial-layers and hierarchical modulation, AT-DMB provides standard definition (SD)-level video while maintaining compatability with the existing CIF-level video. In this paper, we suggest a layer-configuration and coding parameters of SVC which are well suit for an AT-DMB system. In order to reduce extremely large encoding time resulted by an exhaustive search of a macroblock coding mode in spatial scalability, we propose a fast mode decision method which excludes redundant modes in each layer. It utilizes the mode distribution of each layer and their correlations. Experimental results show that a simplified encoding model with the method reduces the computational complexity significantly with negligible coding loss.

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Improved Performance of Very Low Bit-rate Video Coding Using Wavelet Packet Transform

  • Ratansanya, San;Amornraksa, Thumrongrat;Tipakorn, Bundit
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.900-903
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    • 2002
  • This paper proposes the use of wavelet packet transform in a transform based video coding scheme, which is mainly used in low/very low bit-rate video coding schemes i.e. H.263 standard. In the experiments, the discrete cosine transform in the video coding scheme is replaced by the wavelet packet transform, and the improved performance in term of peak signal to noise ratio is measured and compared with the results obtained from the coding scheme implementing the ordinary wavelet transform. The experimental results show an impressive improvement obtained from the use of wavelet packet transform.

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DMB 멀티미디어 서비스를 위한 효율적인 비디오 다중화 방식 (An effective video multiplexing method for the DMB multimedia services)

  • 나남웅;백선혜;홍성훈
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.267-270
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    • 2003
  • The DMB recently standardized in Korea is a Eureka-147 DAB(Digital Audio Broadcasting)-based standard which is able to provide multimedia services including moving pictures, still images, text and etc. That has the structure to add the MPEG media codec and the MPEG system, namely, video-multiplexer to the DAB system. In this paper, we analysis the video-multiplexer of the DMB standard and propose a new multiplexer, namely. M4GM(MPEG-4 General Mux) included in the DMB vido-multiplexer for the performance improvement with respect to the transmission efficiency and the expansible functions. In addition, we simulate the two video-multiplexers and then compare and estimate their performance entirely.

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e-AG를 위한 시공간적 계위를 이용한 3차원 비디오 압축 (3D video coding for e-AG using spatio-temporal scalability)

  • 오세찬;이영호;우운택
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.199-202
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    • 2003
  • In this paper, we propose a new 3D coding method for heterogeneous systems over enhanced Access Grid (e-AG) with 3D display using spatio-temporal scalability. The proposed encoder produces four bit-streams: one base layer and enhancement layer l, 2 and 3. The base layer represents a video sequence for left eye with lower spatial resolution. An enhancement layer l provides additional bit-stream needed for reproduction of frames produced in base layer with full resolution. Similarly, the enhancement layer 2 represents a video sequence for right eye with lower spatial resolution and an enhancement layer 3 provides additional bit-stream needed for reproduction of its reference pictures with full resolution. In this system, temporal resolution reduction is obtained by dropping B-frames in the receiver according to network condition. The receiver system can select the spatial and temporal resolution of video sequence with its display condition by properly combining bit-streams.

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색상 정보를 이용한 반자동 영상분할 기법 (Semi-Automatic Segmentation based on Color Information)

  • 김민호;최재각;호요성
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.619-622
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    • 1999
  • This paper describes a new semi-automatic segmentation algorithm based on color information. Semi-automatic segmentation mainly consists of intra-frame segmentation and inter-frame segmentation. While intra-frame segmentation extracts video objects of interest from boundary information provided by the user and intensity information of the image, inter-frame segmentation partitions the image into the video objects and background by tracking the motion of video objects. For inter-frame segmentation, color information (Y, Cb and Cr) of the current frame can be used efficiently in order to find the exact boundary of the video objects. In this paper we propose a new region growing algorithm which can maximize the ability of region differentiation, while preserving features of each color component.

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비디오 카메라의 효과적인 자동 초점 조절 기술 (Effective Autofousing Technique for Video Camera)

  • 이준석;최강선;고성제
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.617-620
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    • 1999
  • In this paper, a new autofocusing technique which is resistive to noise generated by the CCD of video cameras is proposed. In the proposed scheme, the frequency selective weighted median (FSWM) filter is utilized to estimate the degree of focus and the fast hill-climbing search (HCS) strategy is exploited to determine the best focused image. Since the FSWM filter can not only extract high frequency components from the image, but also eliminate impulsive noise, the proposed autofocusing method employing the FSWM criterion function can estimate the degree of focus precisely. Furthermore, the proposed real-time HCS algorithm enables the video camera to continuously focus on dynamic images. Experimental results demonstrate that the proposed technique outperforms existing techniques by enhancing the accuracy of the focus value of the video camera without the influence of noise.

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인터넷에서의 효율적인 영상 저장 시스템 (An Efficient Video Storage System on the Internet)

  • 이준표;조철영
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2011년도 제43차 동계학술발표논문집 19권1호
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    • pp.293-294
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    • 2011
  • 본 논문에서는 비디오 카메라를 이용하여 촬영한 영상신호의 편집 시스템과 편집 방법, 그리고 효율적인 영상 관리를 수행하는 영상 시스템을 제안한다. 이를 위해 아날로그 비디오 카메라로 촬영한 아날로그 비디오 신호 또는 디지털 비디오 카메라로 촬영한 디지털 비디오 신호를 컴퓨터 시스템을 이용하여 볼 수 있는 비디오 스트림 데이터로 변환시킨다. 컴퓨터 시스템에 구비된 사용자 인터페이스를 이용하여 입력되는 사용자의 요구에 따라 변환된 비디오 스트림 데이터를 내용 또는 일자별로 인덱스화하여 저장하며 사용자가 인덱스 정보를 이용하여 비디오 스트림 데이터들을 검색하고 편집한다.

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