• 제목/요약/키워드: Prediction#4

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Inter-layer Texture and Syntax Prediction for Scalable Video Coding

  • Lim, Woong;Choi, Hyomin;Nam, Junghak;Sim, Donggyu
    • IEIE Transactions on Smart Processing and Computing
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    • 제4권6호
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    • pp.422-433
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    • 2015
  • In this paper, we demonstrate inter-layer prediction tools for scalable video coders. The proposed scalable coder is designed to support not only spatial, quality and temporal scalabilities, but also view scalability. In addition, we propose quad-tree inter-layer prediction tools to improve coding efficiency at enhancement layers. The proposed inter-layer prediction tools generate texture prediction signal with exploiting texture, syntaxes, and residual information from a reference layer. Furthermore, the tools can be used with inter and intra prediction blocks within a large coding unit. The proposed framework guarantees the rate distortion performance for a base layer because it does not have any compulsion such as constraint intra prediction. According to experiments, the framework supports the spatial scalable functionality with about 18.6%, 18.5% and 25.2% overhead bits against to the single layer coding. The proposed inter-layer prediction tool in multi-loop decoding design framework enables to achieve coding gains of 14.0%, 5.1%, and 12.1% in BD-Bitrate at the enhancement layer, compared to a single layer HEVC for all-intra, low-delay, and random access cases, respectively. For the single-loop decoding design, the proposed quad-tree inter-layer prediction can achieve 14.0%, 3.7%, and 9.8% bit saving.

Analysis of low level cloud prediction in the KMA Local Data Assimilation and Prediction System(LDAPS) (기상청 국지예보모델의 저고도 구름 예측 분석)

  • Ahn, Yongjun;Jang, Jiwon;Kim, Ki-Young
    • Journal of the Korean Society for Aviation and Aeronautics
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    • 제25권4호
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    • pp.124-129
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    • 2017
  • Clouds are an important factor in aircraft flight. In particular, a significant impact on small aircraft flying at low altitude. Therefore, we have verified and characterized the low level cloud prediction data of the Unified Model(UM) - based Local Data Assimilation and Prediction System(LDAPS) operated by KMA in order to develop cloud forecasting service and contents important for safety of low-altitude aircraft flight. As a result of the low level cloud test for seven airports in Korea, a high correlation coefficient of 0.4 ~ 0.7 was obtained for 0-36 leading time. Also, we found that the prediction performance does not decrease as the lead time increases. Based on the results of this study, it is expected that model-based forecasting data for low-altitude aviation meteorology services can be produced.

A Fast 4X4 Intra Prediction Method using Motion Vector Information and Statistical Mode Correlation between 16X16 and 4X4 Intra Prediction In H.264|MPEG-4 AVC (H.264|MPEG-4 AVC 비디오 부호화에서 움직임 벡터 정보와 16~16 및 4X4 화면 내 예측 최종 모드간 통계적 연관성을 이용한 화면 간 프레임에서의 4X4 화면 내 예측 고속화 방법)

  • Na, Tae-Young;Jung, Yun-Sik;Kim, Mun-Churl;Hahm, Sang-Jin;Park, Chang-Seob;Park, Keun-Soo
    • Journal of Broadcast Engineering
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    • 제13권2호
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    • pp.200-213
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    • 2008
  • H.264| MPEG-4 AVC is a new video codingstandard defined by JVT (Joint Video Team) which consists of ITU-T and ISO/IEC. Many techniques are adopted fur the compression efficiency: Especially, an intra prediction in an inter frame is one example but it leads to excessive amount of encoding time due to the decision of a candidate mode and a RDcost calculation. For this reason, a fast determination of the best intra prediction mode is the main issue for saving the encoding time. In this paper, by using the result of statistical relation between intra $16{\times}16$ and $4{\times}4$ intra predictions, the number of candidate modes for $4{\times}4$ intra prediction is reduced. Firstly, utilizing motion vector obtained after inter prediction, prediction of a block mode for each macroblock is made. If an intra prediction is needed, the correlation table between $16{\times}16$ and $4{\times}4$ intra predicted modes is created using the probability during each I frame-coding process. Secondly, using this result, the candidate modes for a $4{\times}4$ intra prediction that reaches a predefined specific probability value are only considered in the same GOP For the experiments, JM11.0, the reference software of H.264|MPEG-4 AVC is used and the experimental results show that the encoding time could be reduced by 51.24% in maximum with negligible amounts of PSNR drop and bitrate increase.

The Study on the Prediction and Measurement for the Behaviour of Structures and Weathered Soil & Rock in Excavating the Ventilation Shaft (지하철 개착구 굴착시 주변자반과 구조물에 대한 거동예측과 실측의비교평가)

  • 김융태;안대영;김득기;한창헌
    • Tunnel and Underground Space
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    • 제4권1호
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    • pp.63-76
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    • 1994
  • This paper discusses contents of the existing design, the behaviours prediction on the strut and retaining wall around subsurfaces, and also evaluates the measured results in comparison with the management criterion during excavation period of ventilation shaft at Pusan-Subway 220. Field measurements showed that maximum displacement 23.74 mm at boundary site of multistratification and the weathered rock to be formed at 0.2~0.6 H of total excavating depth(H), 68 ton of maximum axial force and 4.4X102 kg/cm2 of stress on strut. The measured axial force exceeds prediction levels by up to 50 percent at the weathered soil & rock, and the others come under the category of their levels. The great gap of both field measurements and prediction on behaviour makes a difference of the site situation at the design stage and the practical working. This measured value is greatly safety in comparison with that of the safety criterion, but axial force at 4~5 strut of ventilation shaft l is higher than the prediction.

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Uni-directional 8X8 Intra Prediction for H.264 Coding Efficiency (H.264에서 성능향상을 위한 Uni-directional 8X8 인트라 예측)

  • Kook, Seung-Ryong;Park, Gwang-Hoon;Lee, Yoon-Jin;Sim, Dong-Gyu;Jung, Kwang-Soo;Choi, Hae-Chul;Choi, Jin-Soo;Lim, Sung-Chang
    • Journal of Broadcast Engineering
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    • 제14권5호
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    • pp.589-600
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    • 2009
  • This paper is ready to change a trend of a ultra high definition (UHD) video image, and it will contribute to improve the performance of the latest H.264 through the Uni-directional $8{\times}8$ intra-prediction idea which is based on developing a intra prediction compression. The Uni-directional $8{\times}8$ intra prediction is focused on a $8{\times}8$ block intra prediction using $4{\times}4$ block based prediction which is using the same direction of intra prediction. This paper describes that the uni-directional $8{\times}8$ intra-prediction gets a improvement around 7.3% BDBR only in the $8{\times}8$ block size, and it gets a improvement around 1.3% BDBR in the H.264 applied to the multi block size structures. In the case of a larger image size, it can be changed to a good algorithm. Because the video codec which is optimized for UHD resolution can be used a different block size which is bigger than before(currently a minimum of $4{\times}4$ blocks of units).

Intra-Mixture Prediction Mode and Enhanced Most Probable Mode Estimation for Intra Coding

  • Lee, Jin-Ho;Choi, Jin-Soo;Hong, Jin-Woo;Choi, Hae-Chul
    • ETRI Journal
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    • 제31권5호
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    • pp.610-612
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    • 2009
  • We present intra-mixture prediction (IMP) mode for intra prediction and an enhanced estimation method for most probable mode (MPM). IMP mode supports more flexibility in intra prediction by mixing $4{\times}4$ blocks and $8{\times}8$ blocks in one macroblock, while the enhanced MPM estimation extends the number of referenced neighboring blocks and efficiently uses their prediction modes depending on their positions. Simulation results show that the combination of both proposed methods provides a bit reduction in the Bj${\phi}$ntegaard delta bitrate by an average of 2.56% compared to H.264/AVC.

Shear strength prediction for SFRC and UHPC beams using a Bayesian approach

  • Cho, Hae-Chang;Park, Min-Kook;Hwang, Jin-Ha;Kang, Won-Hee;Kim, Kang Su
    • Structural Engineering and Mechanics
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    • 제74권4호
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    • pp.503-514
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    • 2020
  • This study proposes prediction models for the shear strength of steel fiber reinforced concrete (SFRC) and ultra-high-performance fiber reinforced concrete (UHPC) beams using a Bayesian parameter estimation approach and a collected experimental database. Previous researchers had already proposed shear strength prediction models for SFRC and UHPC beams, but their performances were limited in terms of their prediction accuracies and the applicability to UHPC beams. Therefore, this study adopted a statistical approach based on a collected database to develop prediction models. In the database, 89 and 37 experimental data for SFRC and UHPC beams without stirrups were collected, respectively, and the proposed equations were developed using the Bayesian parameter estimation approach. The proposed models have a simplified form with important parameters, and in comparison to the existing prediction models, provide unbiased high prediction accuracy.

Smart Control System Using Fuzzy and Neural Network Prediction System

  • Kim, Tae Yeun;Bae, Sang Hyun
    • Journal of Integrative Natural Science
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    • 제12권4호
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    • pp.105-115
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    • 2019
  • In this paper, a prediction system is proposed to control the brightness of smart street lamps by predicting the moving path through the reduction of consumption power and information of pedestrian's past moving direction while meeting the function of existing smart street lamps. The brightness of smart street lamps is adjusted by utilizing the walk tracking vector and soft hand-off characteristics obtained through the motion sensing sensor of smart street lamps. In addition, the motion vector is used to analyze and predict the pedestrian path, and the GPU is used for high-speed computation. Pedestrians were detected using adaptive Gaussian mixing, weighted difference imaging, and motion vectors, and motions of pedestrians were analyzed using the extracted motion vectors. The preprocessing process using linear interpolation is performed to improve the performance of the proposed prediction system. Fuzzy prediction system and neural network prediction system are designed in parallel to improve efficiency and rough set is used for error correction.

Improving the prediction accuracy by using the number of neighbors in collaborative filtering (협력적 필터링 추천기법에서 이웃 수를 이용한 선호도 예측 정확도 향상)

  • Lee, Hee-Choon
    • Journal of the Korean Data and Information Science Society
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    • 제20권3호
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    • pp.505-514
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    • 2009
  • The researcher analyzes the relationship between the number of neighbors and the prediction accuracy in the preference prediction process using collaborative filtering system. The number of neighbors who are involved in the preference prediction process are divided into four groups. Each group shows a little difference in the preference prediction. By using prediction error averages in each group, linear functions are suggested. Through the result of this study, the accuracy of preference prediction can be raised when using linear functions by using the number of neighbors in the suggested system.

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Effective hardware design for DCT-based Intra prediction encoder (DCT 기반 인트라 예측 인코더를 위한 효율적인 하드웨어 설계)

  • Cha, Ki-Jong;Ryoo, Kwang-Ki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • 제16권4호
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    • pp.765-770
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    • 2012
  • In this paper, we proposed an effective hardware structure using DCT-based inra-prediction mode selection to reduce computational complexity caused by intra mode decision. In this hardware structure, the input block is transformed at first and then analyzed to determine its texture directional tendency. the complexity has solved by performing intra prediction in only predicted edge direction. $4{\times}4$ DCT is calculated in one cycle using Multitransform_PE and Inta_pred_PE calculates one prediction mode in two cycles. Experimental results show that the proposed Intra prediction encoding needs only 517 cycles for one macroblock encoding. This architecture improves the performance by about 17% than previous designs. For hardware implementation, the proposed intra prediction encoder is implemented using Verilog HDL and synthesized with Megnachip $0.18{\mu}m$ standard cell library. The synthesis results show that the proposed architecture can run at 125MHz.