• Title/Summary/Keyword: H.263+

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A Study on Monitoring Technique for Home Server based on Web Camera (웹 카메라 기반 홈 서버용 모니터링 기술에 관한 연구)

  • Jeong Jong-Geun;Cheon Sung-Hwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.8
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    • pp.1754-1761
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    • 2005
  • A monitoring system for the security is increasingly demanded in line with the issue of the infringement of privacy. This paper has conducted the study on the monitoring technique via the Internet using PC or PDA. This is a monitoring system for web-camera based home server, which transmits the images and sound data captured by mike-embedded USB camera, though multiplexer of H.263 and internet. It integrates the operating processors of each device into a unified drive module and provides it the operator to facilitate the system operation and maintenance.

Region-based H.263 Video Codec with Effective Rate Control Algorithm for Low VBR Video

  • Song, Hwangjun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1755-1766
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    • 1999
  • A region-based video codec based on the H.263+ standard is examined and its associated novel rate control scheme is proposed in this work. The region-based coding scheme is a hybrid method that consists of the traditional block DCT coding and the object-based coding. Basically, we adopt H.263+ as the platform, and develop a fast macroblock-based segmentation method to implement the region-based video codec. The proposed rate control solution includes rate control in three levels: encoding frame selection, frame-layer rate control and macroblock-layer rate control. The goal is to enhance the visual quality of decoded frames at low bit rates. The efficiency of proposed rate control scheme applied to the region-based video codes is demonstrated via several typical test sequences.

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Association Study between Porcine LEPR-derived Microsatellite Polymorphisms and Economic Traits (돼지 leptin receptor내 초위성체 다형성과 경제형질과의 연관성 구명)

  • Choi, B.H.;Kim, T.H.;Cho, Y.M.;Lee, H.Y.;Jeon, J.T.;Cheong, I.C.
    • Journal of Animal Science and Technology
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    • v.45 no.5
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    • pp.679-688
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    • 2003
  • The leptin receptor gene(LEPR) produces a high affinity receptor that mediates the regulation of the leptin gene. Leptin secreted from adipose tissue plays an important role in regulating feed intake and energy balance. In this study, a microsatellite marker within LEPR was selected and genotyped for the F2 population composed of 354 individuals from an intercross between Korean Native boars and Landrace sows. Totally, six alleles (255, 259, 261, 263, 265 and 267bp) and nineteen genotypes were detected in the population, of which the CE (261/265), CC (261/261) and EE (265/265) types were observed by 20.0%, 10.1% and 9.6%, respectively. Relationships between their genotypes and economic traits were analyzed. We found specific genotypes associated with economic traits such as body weight at 12 weeks of age/body fat including abdominal and trimmed fat/shear force (P〈0.001), body weight of 30 weeks of age (P〈0.01) and body weight of 3 weeks of age/back fat thickness (P〈0.05). The DD (263/263) and DF (263/267) types were associated with body weight at 3, 5, 12 and 30 weeks of age. The DF (263/267) type showed a highly significant effect on back fat thickness and body fat including abdominal and trimmed fat. The DF (263/267) type showed positive effect on shear force, whereas the BB (259/259) and DD (263/263) types negatively affected on tenderness.

Design of Joint Source-Channel Coder for H.263+ by MAP estimation (H.263+을 위한 MAP기반의 Joint Source-Channel Coder 설계)

  • 송호현;최윤식
    • Proceedings of the IEEK Conference
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    • 2000.11d
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    • pp.171-174
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    • 2000
  • In this paper, We try to design combined source-channel coder that is compatible with video coding standards. This MAP decoder is proposed by adding semantic structure and semantic constraint of video coding standards to the method using redundnacy of the MAP decoders proposed previously. Then, We get the better performance than usual channel coder's.

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Improved SPIHT video coder using Mu1ti-weighting factor (다중 가중 인자를 이용한 개선된 SPIHT 비디오 부호기)

  • 정용재;강경원;서호찬;권기룡;문광석
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.229-232
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    • 2001
  • 초저속 전송 통신망에서 비디오 전송을 효율적으로 하기 위한 시스템은 낮은 비디오 전송율에서 높은 압축율을 갖는 부호화 방법들이 사용된다. 현재 저속 통신을 위한 부호화 표준으로 대표적인 ITU-T의 H.263은 DCT기반이므로 낮은 비트율에서 블록화 현상이 발생한다. 본 논문에서 제안하는 다중 가중 인자를 이용한 SPIHT 비디오 부호기는 H.263에 비하여 동영상의 PSNR이 우수한 성능을 보였고 기존 SPIHT 비디오 부호기보다도 PSNR이 우수함을 확인하였다.

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The Error concealment using Scalability in H.236v2 (H.263v2에서 계층부호화를 이용한 오류 은닉)

  • 한승균;장승기;서덕영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.7A
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    • pp.1063-1075
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    • 2000
  • This paper proposes an adaptive error concealment technique for compressed video. Since redundancy is extracted out during compression process, compressed video is vulnerable to errors which occur during transmission of video over error prone networks such as wireless channels and Internet. Error concealment is a process of reconstructing video out of damaged video bit stream. We proved that scalable encoding is very useful for error concealment. Analysis of experiments shows that some part of image is better concealed by using base layer information and other part of image is better concealed by using previous frame information. We developed a technique which enables to decide which methodology is more effective, adaptively, based on motion vectors and regional spatial activity. We used H.263v2 for scalable encoding, but, our approach could be applied to all DCT based video codec.

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Effects of deck's width-to-depth ratios and turbulent flows on the aerodynamic behaviors of long-span bridges

  • Lin, Yuh-Yi;Cheng, Chii-Ming;Lan, Chao-Yuan
    • Wind and Structures
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    • v.6 no.4
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    • pp.263-278
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    • 2003
  • This study investigates the effects of a bridge deck's width-to-depth (B/H) ratio and turbulence on buffeting response and flutter critical wind speed of long-span bridges by conducting section model tests. A streamlined box section and a plate girder section, each with four B/H ratios, were tested in smooth and turbulent flows. The results show that for the box girders, the response increases with the B/H ratio, especially in the vertical direction. For the plate girders, the vertical response also increases with the B/H ratio. However, the torsional response decreases as the B/H ratio increases. Increasing the B/H ratio and intensity of turbulence tends to improve the bridge's aerodynamic stability. Experimental results obtained from the section model tests agree reasonably with the calculated results obtained from a numerical analysis.

Corrosion Behavior of Superalloys in Hot Molten Salt under Oxidation Atmosphere (고온용융염계 산화분위기에서 초합금의 부식거동)

  • 조수행;임종호;정준호;이원경;오승철;박성원
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.285-291
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    • 2004
  • As a part of assessment of the structural material for the molten salt handling system, corrosion behavior of Inconel 718, X-750, Haynes 75 and Haynes 263 alloys in the molten salt of LiCl-Li$_2$O-O$_2$was investigated in the range of temperature; $650^{\circ}C$, time; 24~168h, $Li_2O$; 3wt%, mixed gas; Ar~10%$O_2$. In the molten salt of LiCl-$Li_2O-O_2$, the order corrosion rate was Haynes 263 < Haynes 75 < Inconel X-750 < Inconel 718. Haynes 263 alloy showed the highest corrosion resistance among the examined alloys. Corrosion products of alloys were as fellows: Haynes 75: $Cr_2O_4$, $NiFe_2O_4$, $LiNiO_2$, $Li_2NiFe_2O_4$, Inconel 718; $Cr_2O_4$, $NiFe_2O_4$, Haynes 263; $Li(Ni,Co)O_2$, $NiCr_2O_4$, $LiTiO_2$, Inconel X-750; $Cr_2O_3$, $NiFe_2O_4$,$FeNi_3$, (Al,Nb,Ti)$O_2$. Haynes 263 showed local corrosion behavior and Haynes 75, Inconel 718 and Inconel X-750 showed uniform corrosion behavior.

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Bitrate Scalable Video Coder (비트율 계위 비디오 부호기)

  • 임범렬;임성호;민병의;황승구;황재정
    • Journal of Broadcast Engineering
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    • v.2 no.2
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    • pp.206-215
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    • 1997
  • We pror.a;e a H.263-based video ceder with two-layer ocalability. The bare layer is ceded by using the default H.263 axling algorithms to achieve high compresred video data and the enhanced layer is axied by enhanced axling such as HVS-based quantization updating. The enhanced layer contains only arled refinement data for the OCT coefficients of the bare layer. Bitstream syntax and semantics for enhancement layer are designed and quantizer design using the HVS is pror.ooed. Data from the two layers are combined after inverse quantization and inverse OCT prcx:esses in the deaxier. We show with e~rirrental results that the pror.a;ed layered arlee achieves comparable picture quality with non-layered arlee at bitrates of 30 kbr;s or less. Overhead information for the bitstream layer can 00 limited to less than 0.5 kbits/frame.

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