• Title/Summary/Keyword: H Mode

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Scene change detection using intra prediction mode and edge direction in H.264/AVC compression domain (압축 영역에서 intra mode와 에지 방향성을 이용한 H.264 비디오 장면 전환 검출)

  • Hong, Bo-Hyun;Eom, Min-Young;Choe, Yoon-Sik
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.12-14
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    • 2006
  • This paper presents a novel scene change detection method using intra prediction mode and edge direction in H.264/AVC. When scene change occurs, there are less temporal correlation between frames, most of macro-blocks encoded in intra mode. Using this property, the method calculates the percentage of intra mode blocks in each predictive frame in order to get candidates of scene change frame. To further find scene change, we obtain edge histogram of each candidates by using eight prediction direction of intra prediction mode in H.264/AVC. We detect scene change frames with $\iota^1$-norm of edge histograms. The experimental results show that the method is efficient and robust.

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Performance Efficiency of Compound CVTs with a 2K-H II (2K-H II 형식 복합형 무단변속기의 효율실험)

  • Park J.M.;Kim Y.S.;Lee S.H.;Choi S.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.670-673
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    • 2005
  • We designed the compound CVT (Continuously Variable Transmissions) by combining power circulation mode CVT and power split mode CVT, which have been proposed for connecting 2K-H II differential gear to the V- belt type CVU (Continuously Variable Unit), as an input coupled type. With the designed compound CVT, we carried out theoretical analysis and performance experiments. We proved that the compound CVT had a better performance than either of the power circulation mode or power split mode.

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Fast Mode Decision in H.264/AVC Using Adaptive Selection of Reference Frame and Selective Intra Mode (다중 참조 영상의 적응적 선택 및 선택적 인트라 모드를 이용한 H.264/AVC의 고속 모드 결정 방법)

  • Lee Woong-Ho;Lee Jung-Ho;Cho Ik-Hwan;Jeong Dong-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.3C
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    • pp.271-278
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    • 2006
  • Rate-constrained coding is one of the many coding-efficiency oriented tools of H.264/AVC, but mode decision process of RDO(Rate distortion optimization) requires high computational complexity. Many fast mode decision algorithms have been proposed to reduce the computational complexity of mode decision. In this paper, we propose two algorithms for reduction of mode decision in H.264/AVC, which are the fast reference frame selection and selective intra prediction mode decision. Fast reference frame selection is efficient for inter predication and selective intra prediction mode decision can effectively reduce excessive calculation load of intra prediction mode decision. The simulation results showed that the proposed methods could reduce the encoding time of the overall sequences by 44.63% on average without any noticeable degradation of the coding efficiency.

Fast Intra Mode Selection Algorithm for H.264/AVC Using Constraints of Frequency Characteristics (주파수 특성의 제약 조건들을 이용한 H.264/AVC를 위한 고속 화면 내 모드 선택 방법)

  • Jin, Soon-Jong;Park, Sang-Jun;Jeong, Je-Chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.4C
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    • pp.321-329
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    • 2008
  • H.264/AVC video coding standard enables a considerably higher improvement in coding efficiency compared with previous standards such as MPEG-2, H.263 and MPEG-4. To achieve this, for each macro-block in H.264/AVC, Rate-Distortion Optimization (RDO) technique is employed to select the best motion vector, reference frame, and macro-block mode. As a result, computational complexity is increased significantly whereas RDO achieve higher improvement. This paper presents fast intra mode selection algorithm based on constraints of frequency characteristics which are derived from intra coding modes of H.264/AVC. First of all, we observe the features of each intra mode through the frequency analysis of image. And then proposed Frequency Error Costs (FECs) are calculated to select the best mode which has minimum cost. Computational complexity is considerably reduced because rate-distortion costs only calculate the candidate modes which are set of best mode and its neighbouring two modes. Experimental results show that proposed algorithm reduces the complexity dramatically maintaining the rate-distortion performance compared with H.264/AVC reference software.

다양한 가스를 이용한 유도 결합 플라즈마에서 E-H mode 전이 현상

  • Lee, Jeong-Gyu;Lee, Hyo-Chang;Jeong, Jin-Uk
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.439-439
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    • 2010
  • 다양한 가스 방전에서의 전자에너지 분포함수 측정을 통하여 E-H mode 전이에 대한 연구를 하였다. 단원자 가스 방전에서는, 압력이 증가함에 따라 E-mode에서 H-mode로의 전이를 위한 인가 파워는 크게 바뀌지 않았다. 하지만, 다원자 가스에서는 압력이 증가함에 따라 상당히 높은 인가 파워가 필요하였다. 이것은 다원자 가스에서 압력이 증가함에 따라, 해리, 진동 및 회절 운동, 그리고 음이온 생성으로 인한 플라즈마 밀도의 감소에 의한 것이다. 그에 따라, H-mode 전이를 위한 충분한 플라즈마 밀도를 생성하기 위해서 더 큰 인가 파워가 필요하게 된다. 이러한 연구는 혼합가스에서도 측정하였다.

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Hydrogen Plasma Characteristics for Photoresist Stripping Process in a Cylindrical Inductively Coupled Plasma

  • Yang, Seung-Kook;Cho, Jung Hee;Lee, Seong-Wook;Lee, Chang-Won;Park, Sang-Jong;Chae, Hee-Sun
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.4
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    • pp.387-394
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    • 2013
  • As the feature size of integrated circuits continues to decrease, the challenge of achieving an oxidation-free exposed layer after photoresist (PR) stripping is becoming a critical issue for semiconductor device fabrication. In this article, the hydrogen plasma characteristics in direct plasma and the PR stripping rate in remote plasma were studied using a $120{\Phi}$ cylindrical inductively coupled plasma source. E mode, H mode and E-H mode transitions were observed, which were defined by matching the $V_{rms}$ and total impedance. In addition, the dependence of the E-H mode transition on pressure was examined and the corresponding plasma instability regions were identified. The plasma density and electron temperature increased gradually under the same process conditions. In contrast, the PR stripping rate decreased with increasing proportion of $H_2$ gas in mixed $H_2/N_2$ plasma. The decrease in concentration of reactive radicals for the removal of PR with increasing $H_2$ gas flow rate suggests that NH radicals have a dominant effect as the main volatile product.

Normal Mode Approach to the Stability Analysis of Rossby-Haurwitz Wave

  • Jeong, Hanbyeol;Cheong, Hyeong Bin
    • Journal of the Korean earth science society
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    • v.38 no.3
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    • pp.173-181
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    • 2017
  • The stability of the steady Rossby-Haurwitz wave (R-H wave) in the nondivergent barotropic model (NBM) on the sphere was investigated with the normal mode method. The linearized NBM equation with respect to the R-H wave was formulated into the eigenvalue-eigenvector problem consisting of the huge sparse matrix by expanding the variables with the spherical harmonic functions. It was shown that the definite threshold R-H wave amplitude for instability could be obtained by the normal mode method. It was revealed that some unstable modes were stationary, which tend to amplify without the time change of the spatial structure. The maximum growth rate of the most unstable mode turned out to be in almost linear proportion to the R-H wave amplitude. As a whole, the growth rate of the unstable mode was found to increase with the zonal- and total-wavenumber. The most unstable mode turned out to consist of more-than-one zonal wavenumber, and in some cases, the mode exhibited a discontinuity over the local domain of weak or vanishing flow. The normal mode method developed here could be readily extended to the basic state comprised of multiple zonalwavenumber components as far as the same total wavenumber is given.

A Fast Inter Mode Decision Algorithm Considering Quantization Parameter in H.264 (H.264 표준에서 양자화 계수를 고려한 고속 인터모드 결정 방법)

  • Kim, Geun-Yong;Ho, Yo-Sung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.6 s.312
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    • pp.11-19
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    • 2006
  • The recent video coding standard H.264 employs the rate-distortion optimization (RDO) method for choosing the best coding mode; however, it causes a large amount of encoding time. Thus, in order to reduce the encoding time, we need a fast mode decision algorithm. In this paper, we propose a fast inter mode decision algorithm considering quantization parameter (QP). The occurrence of best modes depends on QP. In order to reflect these characteristics, we consider the coded block pattern (CBP) which has 0 value when all quantized discrete cosine transform (DCT) coefficients are zero. We also use the early SKIP mode decision and early $16{\times}16$ mode decision methods. By computer simulations, we have verified that the proposed algorithm requires less encoding time than the fast inter mode decision method of the H.264 reference software for the Baseline and Main profiles by 19.6% and 18.8%, respectively.

A Hierarchical Mode Decision Method for H.264 Intra Image Coding

  • Liu, Jiantan;Yoo, Kook-Yeol
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.297-300
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    • 2007
  • Due to its impressive compression performance, the H.264 video coder is highlighted in the video communications industry, such as DMB (Digital Multimedia Broadcasting), PMP (Portable Multimedia Player), etc. The main bottleneck to use the H.264 coder lays in the computational complexity, i.e. five times more complex than the market leading MPEG-4 Simple Profile codec. In this paper, we propose the hierarchical mode decision method for intraframe coding for the reduction of the computation complexity of the encoder. By determining the mode group early, the propose algorithm can skip the computationally demanding computation in the mode decision. The proposed algorithm is composed of three steps: $16{\times}16$ mode decision, $4{\times}4$ mode-group decisions, and final mode decision among the selected mode group. The simulation results show that the proposed algorithm achieves 20% to 50% reduction in the computational complexity compared with the conventional algorithm.

Fast Coding Mode Decision for Temporal Scalability in H.264/AVC Scalable Extension (시간적 계층에서의 스케일러블 부호화 고속 모드 결정 방법)

  • Jeon, Byeungwoo
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.6 no.2
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    • pp.71-75
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    • 2013
  • Recently proliferating heterogeneous multimedia service environments should be able to deal with many different transmission speeds, image sizes, or qualities of video. However, not many existing video compression standards satisfy those necessities. To satisfy the functional requirements, the standardization of the H.264/AVC Scalable Extension (SE) technique has been recently completed. It is an extension of the H.264/AVC which can encode several image sizes and qualities at the same time as a single bitstream. To perform optimum mode decision, motion estimation is performed for all MB modes, and the RD costs are compared to identify an MB mode with the smallest RD cost. This increases computational complexity of H.264/AVC SE encoding. In this paper, we propose an early skip mode detection scheme to reduce candidate modes and suggest an algorithm of fast mode decision utilizing reference modes according to the mode history.