Adaptive Error Concealment Algorithm Research Articles

Pixel-level Matching Based Multi-hypothesis Error Concealment Modes for Wireless 3D H.264/MVC Communication

3D multi-view video (MVV) is multiple video streams shot by several cameras around a single scene simultaneously. Therefore it is an urgent task to achieve high 3D MVV compression to meet future bandwidth constraints while maintaining a high reception quality. 3D MVV coded bit-streams that are transmitted over wireless network can suffer from error propagation in the space, time and view domains. Error concealment (EC) algorithms have the advantage of improving the received 3D video quality without any modifications in the transmission rate or in the encoder hardware or software. To improve the quality of reconstructed 3D MVV, we propose an efficient adaptive EC algorithm with multi-hypothesis modes to conceal the erroneous Macro-Blocks (MBs) of intra-coded and inter-coded frames by exploiting the spatial, temporal and inter-view correlations between frames and views. Our proposed algorithm adapts to 3D MVV motion features and to the error locations. The lost MBs are optimally recovered by utilizing motion and disparity matching between frames and views on pixel-by-pixel matching basis. Our simulation results show that the proposed adaptive multi-hypothesis EC algorithm can significantly improve the objective and subjective 3D MVV quality.

Adaptive Error Concealment Technology Based on H.264 for Digital Satellite Set-Top Boxes

In order to improve the decoding performance of digital satellite set-top boxes, this paper proposed a directional boundary matching algorithm on temporal domain for H.264, it considers using the spatial smoothing of video images and the movement consistency in neighbor macro-blocks to restore the damaged macro-block, with pixels matching in three directions on the boundary. On this basis, a adaptive error concealment algorithm of multi-mode is proposed, which avoids the judgment of the partition mode of damaged macro-block. Experimental results show that when in the same case of packet loss, compared with the traditional concealment algorithms, the algorithm proposed in this paper has better performance in the improvement of PSNR and visual effect.

Adaptive error concealment algorithm based on residual distribution for whole frame losses in H.264

The H.264 communication over network may cause a whole frame loss.To solve the problem,an error-concealment algorithm based on residual distribution was proposed for whole frame packet loss in H.264.Firstly,the residual information of reference frame was analyzed.Then,according to the result,the motion vector copy algorithm was used in the region where the image was smooth or the image object's motion was rigid.For the other regions,the motion vector of each pixel was re-estimated,and then optical flow algorithm was introduced.Experimental results show that the algorithm outperforms the traditional one on both visual quality and Peak Signal-to-Noise Ratio(PSNR).

An error resilient video coding and transmission solution over error-prone channels

With the rapid development of network and multimedia technology, the error control in video coding and video transmission over error-prone channels has become increasingly important. The DCT based predictive coding and VLC based entropy coding greatly increase the coding efficiency, but make the compressed video stream very sensitive to transmission errors. Therefore, this paper proposes a reliable error resilient video coding and video transmission framework. In order to improve the robustness to packet loss errors, an error resilient video coding algorithm named Z-FMO is proposed. Some channel may bring random bit errors, an adaptive error concealment algorithm based on macroblock boundary gradient namely ECMBG is proposed aiming at such problem. As the indispensable part of a video transmission system, we implement an adaptive video transmission control algorithm JCBAF. Experimental results show that the proposed framework performs well both in R-D performance and subjective quality.

Temporal Error Concealment for MPEG-Coded Video over Error-Prone Networks

Compressed video streams that transmitted over error prone networks may suffer severe degradation. Error concealment (EC) is one practical approach to combat with the error propagation. A number of EC techniques have been developed to diminish the influence of transmission errors. However, the techniques are always inefficient when the motions of object in a video are fast or complex. This paper proposes an adaptive temporal EC algorithm to precisely conceal the errors for MPEG-coded video. In the proposed method, each damaged macroblock is first divided into four equal sized sub-blocks. Both of the undamaged motion vectors and gray intensity information surrounding a damaged macroblock are performed to reconstruct the lost motion vectors of the sub-blocks based on boundary matching technique. Then the estimated motion vectors are utilized to reconstruct the damaged macroblock by exploiting the information from reference frames. Experimental results show that the visual quality and the PSNR evaluation of reconstructed frames are significantly improved by using the proposed EC algorithms. Thus the proposed method is expected to be a useful EC algorithm for motion vector compressed video over an error-prone network.