• Title/Summary/Keyword: error concealment

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A Spatial Error Concealment Technique Using Edge-Oriented Interpolation (방향성 보간을 이용한 공간적 에러 은닉 기법)

  • Yoo Hyun sun;Kim Won ki;Jeong Je chang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.3C
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    • pp.133-140
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    • 2005
  • This paper introduces a spatial error concealment technique using directional interpolation in block-based compression. The first step involves finding the spatial direction vectors represented an edge-direction in the lost block using spatial boundary matching algorithm. Then, the error blocks are recovered by directional interpolation through these vectors and concealed by using the recovered blocks which have lower directional boundary matching error out of them relatively. This proposed method is able to deal with errors on macroblock or slice level adaptively. And it has lower complexity and maintains better performance compared to the conventional methods.

Region-Based Error Concealment of Depth Map in Multiview Video (영역 구분을 통한 다시점 영상의 깊이맵 손상 복구 기법)

  • Kim, Wooyeun;Shin, Jitae;Oh, Byung Tae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.12
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    • pp.2530-2538
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    • 2015
  • The pixel value of depth image is depth value so that different objects which are placed on nearby position have similar pixel value. Moreover, the pixels of depth image have distinct pixel values compared to adjacent pixels while those of color image has very similar values. Accordingly distorted depth image of multiview video plus depth (MVD) needs proper error concealment methods considering the characteristics of depth image when transmission errors are happened. In this paper, classifying regions of depth image to consider edge directions and then applying adaptive error concealment methods to each region are proposed. Recovered depth images utilize with multiview video data to synthesize intermediate-view point video. The synthesized view is evaluated by objective quality metrics to demonstrate proposed method performance.

Error Concealment Technique for Erroneous Video Using Overlapped Block Motion Compensation (중복 블록 움직임 보상을 이용한 손상된 비디오의 오류 은폐 기법)

  • 김주현;홍원기;고성제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.7B
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    • pp.1384-1392
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    • 1999
  • A high compression rate is required to transmit video sequences over low bit rate networks such as low bit rate communication channels. When highly compressed videos are transmitted over mobile channels of high error rate, bitstreams corrupted by channel errors are not only difficult to be decoded, but also have fatal effects on the other parts of the bitstreams. In this Paper, we propose an error concealment algorithm for recovering the blocks which can not be decoded due to damaged bitstreams. The proposed error concealment algorithm recovers the damaged blocks using the information of adjacent blocks which are correctly decoded. In the proposed algorithm, the motion vector of the damaged block is estimated using the overlapped block motion compensation(OBMC) and block boundary matching(BBM) techniques. Experiment results show that the proposed algorithm exhibits better performance in PSNR than existing error concealment methods.

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Interpolation Error Concealment Method of Motion Compensated Interpolated Frame for Motion Compensated Frame Rate Conversion (움직임 보상 프레임 율 변환 기법을 위한 움직임 보상 보간 프레임의 보간 오류 은닉 기법)

  • Lee, Jeong-Hun;Han, Dong-Il
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.927-928
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    • 2008
  • In this paper, a interpolation error concealment algorithm of motion compensated interpolated frame for motion compensated frame rate conversion to reduce the block artifacts caused by failure of conventional motion estimation based on block matching algorithm is proposed. Experimental results show good performance of the proposed scheme with significant reduction of the block artifacts.

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Error Concealment Based on Semantic Prioritization with Hardware-Based Face Tracking

  • Lee, Jae-Beom;Park, Ju-Hyun;Lee, Hyuk-Jae;Lee, Woo-Chan
    • ETRI Journal
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    • v.26 no.6
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    • pp.535-544
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    • 2004
  • With video compression standards such as MPEG-4, a transmission error happens in a video-packet basis, rather than in a macroblock basis. In this context, we propose a semantic error prioritization method that determines the size of a video packet based on the importance of its contents. A video packet length is made to be short for an important area such as a facial area in order to reduce the possibility of error accumulation. To facilitate the semantic error prioritization, an efficient hardware algorithm for face tracking is proposed. The increase of hardware complexity is minimal because a motion estimation engine is efficiently re-used for face tracking. Experimental results demonstrate that the facial area is well protected with the proposed scheme.

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Adaptive Error Concealment Technique using a Variable Operating Region Algorithm based on MPEG-4 Coding (연산 영역 가변 알고리즘을 적용한 MPEG-4 부호화 기반의 적응적 오류 은닉 기법)

  • 김병주;권기구;이석환;권성근;김봉석;이건일
    • Journal of Korea Multimedia Society
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    • v.6 no.1
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    • pp.78-88
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    • 2003
  • A novel adaptive error concealment technique is proposed using a variable operating region algorithm based on MPEG-4 coding. In the algorithm, a missing block is classified as flat or edge block based on local information from the surrounding blocks extracted using a Sobel operation in a variable operating region (VOR). In this case, the VOR is determined adaptively according to the number of edge directions in the missing block. 1;sing the classification, the flat blocks are then concealed by the Proposed mean based weighted bilinear interpolation (MWBLI) method, and the edge blocks by the boundary directional interpolation (BDI) method. Consequently, the use of the Proposed VOR improves the subjective performance in a curved edge region, while the adaptive processing based on block classification improves the objective performance. Experimental results confirmed that the proposed algorithm produced better results than conventional algorithms, both subjectively and objectively.

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Error-Resilient Video Transmission Techniques over Unreliable Networks (비 신뢰성 네트워크에서 에러를 극복하는 비디오 전송 기법)

  • 노경택
    • Journal of the Korea Society of Computer and Information
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    • v.6 no.3
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    • pp.50-55
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    • 2001
  • We review error resilience techniques for real-time video transport over unreliable networks. For error control on the source coding level, each decoder has to make provisions for error detection, resynchronization. and error concealment. and we review techniques suitable for that purpose. Further, techniques are discussed for intelligent processing of acknowledgment information by the coding control to adapt the source coder to the channel. We review and compare error tracking, error confinement. and reference picture selection techniques for channel-adaptive source coding. We review how feedback-based source codings are related with the precompressed video stored on a media server

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Error Concealment Using Intra-Mode Information Included in H.264/AVC-Coded Bitstream

  • Kim, Dong-Hyung;Jeong, Se-Yoon;Choi, Jin-Soo;Jeon, Gwang-Gil;Kim, Seung-Jong;Jeong, Je-Chang
    • ETRI Journal
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    • v.30 no.4
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    • pp.506-515
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    • 2008
  • The H.264/AVC standard has adopted new coding tools such as intra-prediction, variable block size, motion estimation with quarter-pixel-accuracy, loop filter, and so on. The adoption of these tools enables an H.264/AVC-coded bitstream to have more information than was possible with previous standards. In this paper, we propose an effective spatial error concealment method with low complexity in H.264/AVC intra-frame. From information included in an H.264/AVC-coded bitstream, we use prediction modes of intra-blocks to recover a damaged block. This is because the prediction direction in each prediction mode is highly correlated to the edge direction. We first estimate the edge direction of a damaged block using the prediction modes of the intra-blocks adjacent to a damaged block and classify the area inside the damaged block into edge and flat areas. Our method then recovers pixel values in the edge area using edge-directed interpolation, and recovers pixel values in the flat area using weighted interpolation. Simulation results show that the proposed method yields better video quality than conventional approaches.

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An Efficient Error Concealment Method Using Difference Values of Border Pixels (경계 화소의 차분값을 이용한 효과적인 에러 은닉 방법)

  • Hyun, Seung-Hwa;Kim, Sang-Soo;Kim, Yoo-Shin;Eom, Il-Kyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.5
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    • pp.143-150
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    • 2009
  • In this paper, we present a spatial domain error concealment method to recover a lost block in intra-coded frames. The edge directions of the lost block are estimated by the difference values of the border pixels of the accurately received blocks. The lost block is interpolated according to the estimated edge directions. Our algorithm can adaptively recover a lost block according to the estimated edge direction. The distances between pixels are used as weights for interpolation. In spite of the low computational cost, the proposed method outperforms the previous methods in objective and subjective qualities.

Error Resilient and Concealment Schemes for Still Image Transmission over DSRC System Channel (DSRC시스템 채널 환경에서 정지 영상 전송을 위한 에러 복구 및 은닉 기법)

  • 최은석;백중환
    • Proceedings of the IEEK Conference
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    • 2001.06d
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    • pp.13-16
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    • 2001
  • In the Dedicated Short Range Communication (DSRC) system channel, a large number of bit errors occur because of Additive White Gaussian Noise (AWGN) and fading. When an image data is transmitted under the condition, reconstructed image quality is significantly degraded. In this paper, as an alternative to the error correcting code and/or automatic repeat request scheme, we propose an error recovery scheme for image data transmission. We first analyze how transmission errors in the DSRC system channel degrade image quality. Then, in order to improve image quality, we propose error resilient and concealment schemes for still image transmission using DCT-based fixed length coding, hamming code, cyclic redundancy check, and interleaver. Finally, we show its performance by an experiment.

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