• Proceedings of the IEEK Conference
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• 2000.11d
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• pp.109-112
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• 2000

Bitstrems corrupted by channel errors are not only difficult to be decoded but also propagate error to other part of the bitstreams when highly compressed video is transmitted over channels with noise such as mobile communication channels. In this paper, error concealment algorithm performed in decoder is proposed when errors occur for transmission. Proposed algorithm searches moving area with homogeneous movement in neighbored blocks when motion vectors are damaged, then recovers motion vectors of missing blocks considering where missing blocks are belong to. Experiment result shows that proposed algorithm exhibits better performance in PSNR than existing error concealment method.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.31-39
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• 2003

The MPEG-2 source coding algorithm is very sensitive to transmission errors due to using of variable-length coding. When the compressed data are transmitted, transmission errors are generated and error correction scheme is not able to be corrected well them. In the decoder error concealment (EC) techniques must be used to conceal errors and it is able to minimize degradation of video quality. The proposed algorithm is method to conceal successive macroblock errors of I-frame and utilize temporal information of B-frame and spatial information of P-frame In the previous GOP which is temporally the nearest location to I-frame. This method can improve motion distortion and blurring by temporal and spatial errors which cause at existing error concealment techniques. In network where the violent transmission errors occur, we can conceal more efficiently severe slice errors. This algorithm is Peformed in MPEG-2 video codec and Prove that we can conceal efficiently slice errors of I-frame compared with other approaches by simulations.

• ETRI Journal
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• v.29 no.3
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• pp.390-392
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• 2007

In this paper, we propose a new error concealment (EC) method using inter-layer correlation for scalable video coding. In the proposed method, the auxiliary motion vector (MV) and the auxiliary mode number (MN) of intra prediction are interleaved into the bitstream to recover the corrupted frame. In order to reduce the bit rate, the proposed method encodes the difference between the original and the predicted values of the MV and MN instead of the original values. Experimental results show that the proposed EC outperforms the conventional EC by 2.8 dB to 6.7 dB.

• Proceedings of the IEEK Conference
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• 2000.11c
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• pp.89-92
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• 2000

The wireless network has bursty and high error rates. Due to the quite limited bandwidth in wireless networks, images are usually transmitted as a compressed version with VLC(variable length coding). Loss of coded data can affect a decoded image to a large extent, making concealment of errors caused by data loss an important issue. This paper presents a error concealment technique for DCT(Discrete Cosine Transform) based image coding. First, a method to estimate the missing DC coefficients of a JPEG coded image which is required for decoding the compressed image, is suggested and evaluated. Second, the missing data is interpolated by exploiting the probability of being nonzero and the correlation between adjacent blocks. In addition, since the these technique is computational efficient, it conserves system resources and power consumption, which are restrictive in mobile computers.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.594-597
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• 2003

In this paper, we propose a new temporal error concealment method for recovery of video packet loss. Error concealment for each loss block is performed by temporal motion compensation and a smoothing operation of boundary pixels between the compensated block and its surrounding blocks. In the simulation results, performance improvement for the proposed technique is on the average 2 dB in comparison with the conventional technique.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.9
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• pp.4375-4388
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• 2018

To solve the problem of transmission errors in stereoscopic images, this paper proposes a novel error concealment (EC) method using superpixel segmentation and adaptive disparity selection (SSADS). Our algorithm consists of two steps. The first step is disparity estimation for each pixel in a reference image. In this step, the numbers of superpixel segmentation labels of stereoscopic images are used as a new constraint for disparity matching to reduce the effect of mismatching. The second step is disparity selection for a lost block. In this step, a strategy based on boundary smoothness is proposed to adaptively select the optimal disparity which is used for error concealment. Experimental results demonstrate that compared with other methods, the proposed method has significant advantages in both objective and subjective quality assessment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1708-1713
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• 2003

In this paper, we propose a new temporal error concealment method for video packet loss. Error concealment for each loss block is performed by temporal motion compensation and a spatial smoothing operation of boundary pixels between the compensated block and its surrounding blocks. In the simulation results, performance improvement for the proposed technique is on the average 2㏈ in comparison with conventional techniques.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.349-350
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• 2009

In this paper, we describe an error concealment techniques based on image inpainting for the image impairments due to the packet loss. Image inpainting is to remove or restore the damaged sections from the images, which is usually old images, paintings, or video films. Inpainting has a long history which goes back to the era when the paintings come out. Manual inpainting is no more used, and we can use digital inpainting for the digitally impaired images and video sequences. In this paper, we review the error concealment techniques for the packet loss recovery and propose our inpainting based image impairment recovery scheme for video communication over packet networks.

• ETRI Journal
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• v.31 no.1
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• pp.21-30
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• 2009

In low bit-rate video transmission, the payload of a single packet can often contain a whole coded frame due to the high compression ratio in both spatial and temporal domains of most modern video coders. Thus, the loss of a single packet not only causes the loss of a whole frame, but also produces error propagation into subsequent frames. In this paper, we propose a novel whole frame error concealment algorithm which reconstructs the first of the subsequent frames instead of the current lost frame to suppress the effects of error propagation. In the proposed algorithm, we impose a constraint which uses side match distortion (SMD) and overlapped region difference (ORD) to estimate motion vectors between the target reconstructed frame and its reference frame. SMD measures the spatial smoothness connection between a block and its neighboring blocks. ORD is defined as the difference between the correlated pixels which are predicted from one reference pixel. Experimental results show that the proposed algorithm effectively suppresses error propagation and significantly outperforms other conventional techniques in terms of both peak signal-to-noise ratio performance and subjective visual quality.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.44 no.1
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• pp.94-101
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• 2007

Streaming video is expected to become a key service in the developing heterogeneous wireless network. However, sufficient quality of service is not offered to video applications because of bursty packet losses. An effective solution for packet loss in wireless network is to perform a proper concealment at the receiver. However, most concealment methods can not conceal effectively the consecutively damaged macro blocks, since the neighboring blocks are lost. In the previous work, bidirectional motion vector tracking (BMVT) method has been proposed which uses the moving trajectory feature of the damaged macro blocks. In this paper, a channel-adaptive redundancy coding method for the better BMVT error concealment is presented. The proposed method provides enhanced video quality at the cost of a little bit overhead in the wireless error-prone network.