The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform

Yun He - One of the best experts on this subject based on the ideXlab platform.

  • Short Communication: A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment.

  • A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment. © 2012 Elsevier Inc. All rights reserved.

Yunfei Wang - One of the best experts on this subject based on the ideXlab platform.

  • Short Communication: A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment.

  • A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment. © 2012 Elsevier Inc. All rights reserved.

Jianwen Chen - One of the best experts on this subject based on the ideXlab platform.

  • Short Communication: A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment.

  • A pixel-wise directional intra prediction method
    Journal of Visual Communication and Image Representation, 2012
    Co-Authors: Yunfei Wang, Jianwen Chen, Yun He
    Abstract:

    In a decade where the prominence of video applications has become increasingly prevalent, the optimization of video coding processes remains as important as ever. The directional intra prediction has been proved as an effective tool for intra picture coding. However, in a directional intra prediction based coding structure, there is a considerable gap between the transform efficiency of DCT and the optimal transform KLT. In this paper, we analyze these problems and propose a pixel-wise directional intra prediction (PDIP) method to solve this problem. This method exploits the Reconstruction Value of the adjacent pixels to predict the current pixel, and keeps the block-based lossy coding structure of H.264/AVC. The proposed method can significantly improve the coding efficiency with little decoding complexity increment. © 2012 Elsevier Inc. All rights reserved.

J.a b Yang - One of the best experts on this subject based on the ideXlab platform.

  • CS-UWB channel estimation through adaptive projection
    Journal of Computational Information Systems, 2013
    Co-Authors: J.a b Yang, G.a Zhen, H.a b Yin, S.a b Wang, W.a b Wang
    Abstract:

    Accurate channel estimation of Ultra-wideband (UWB) signal is important, due to its low power spectrum density and complicated transfer multi-path. Considering its wider band width, Compressed Sensing (CS) provides a feasible way of sub-sampling. Common projection matrices are highly relevant with UWB sparse transform matrix, This demanded higher compression ratio which means that sampling speed can not be lowered. To solve these problems, an CS-UWB channel estimation method based on devise adaptive projection matrix is proposed in this paper. Posterior probability density function controlled by hyper-parameters is set to each Value in channel vector. Use its covariance matrix to compute new projection vector. The differential entropy of Reconstruction Value can be decreased. Experimental result shows that the proposed method can decrease the sampling speed notably compared to existing CS-UWB channel estimation method.

Wang Weidong - One of the best experts on this subject based on the ideXlab platform.

  • UWB channel estimation through compressed sensing based on adaptive projection matrix
    Journal of Circuits and Systems, 2013
    Co-Authors: Wang Weidong
    Abstract:

    Due to the low power spectrum density and complicated transfer multi-path of Ultra-Wideband(UWB) signal,it is important to do channel estimation accurately.But it’s difficult to sample it directly as its wider band width.However,compressed sensing(CS) provides a feasible way with lower sampling speed.Common random projection matrix remains high coherence with UWB channel sparse transform matrix and this leads the algorithm achieve Reconstruction requirement only at high compressing ratio,which means that it still needs a high sampling speed.To solve these problems,an UWB channel estimation method based on an adaptive projection matrix using bayesian compressed sensing(BCS) is proposed in this paper.BCS sets posterior probability density function which is controlled by hyperparameters to each Value in the channel vector and computes its statistical characteristics.Using covariance matrix to reckon new projection vector which can lower the differential entropy of Reconstruction Value steepest.This method enhances the certainty of Reconstruction Value and lowers the sampling speed using fewer samples.The experimental results show that this method can achieve a better Reconstruction performance compared to the existing CS Reconstruction algorithm at low compressing ratio and decrease the sampling speed notably.