• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11C
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• pp.1068-1075
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• 2005

In this paper we propose a video coding method and associated packetization and decoding methods for error resilient transmission over the Internet. The proposed method re-organizes the input image into several mutually similar subimages. For this case, if the one of the subimage is lost in the network, the lost one is recovered by the proposed error concealment method which uses the correctly received other subimages. The performance of the proposed method is confirmed by the empirical results. The proposed method is not limited to the Internet communications but is applicable to the other packet-based networks.

• Journal of Broadcast Engineering
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• v.18 no.6
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• pp.872-883
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• 2013

In this paper, we design and analyze performance of Exclusive-OR based FEC (Forward error correction) system to deploy SVC video transmission service over packet-loss prone IP network. In the designed system, we adopt standard compliant Exclusive-OR based FEC scheme and apply it to be appropriate to the hierarchical layer structure of SVC video. To verify the performance of the designed Exclusive-OR based FEC system for SVC video transmission, we employ NIST-NET based transport simulator. By the SVC video transmission using the NIST-NET based simulator, we confirm the error resilient transmission performance of the designed Exclusive-OR based FEC system.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.167-169
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• 2005

The occurrence of a single bit error in transmission bitstream leads to serious temporal and spatial errors. Because moving picture coding as MPEG-2 based on block coding algorithm uses variable length coding and motion compensation coding algorithm. In this paper, we propose algorithm to conceal occurred error of I-frames in transmission channel using data of the neighboring blocks in decoder. We divide a damaged macroblock of I-frame into four sub blocks and compose new macroblock using the neighboring blocks for each sub block. We estimate the block with minimum difference value through block matching with previous frame for new macroblocks and replace each estimated block with damaged sub block in the same position. Through simulation results, the proposed algorithm will be applied to a characteristic of moving with effect and shows better performance than conventional error concealment algorithms from visual and PSNR of view.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3A
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• pp.325-333
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• 2000

The proposed RPSS(Reference Picture Segment Selection) mode is the RPS mode in picture segment of the ISD mode. The RPS mode has the weakness that it has to change the whole reference picture even if transmission error occurs only in the small part of picture. If the RPS mode is applied only to an error-occurred part and a conventional coding scheme is applied to an error-free part, the higher coding efficiency can be obtained. Simulation results show that there is the optimal number of segment which provides that best performance with given environment such as the BER(Bit Error Rate) of wireless channels, the characteristics of imput sequence, what kind of RPSS mode is used, etc. To apply the channel-adoptive RPSS mode later, the scheme which can change the number of segment without INTRA refresh and spatial error propagation is proposed in this paper.

• Proceedings of the IEEK Conference
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• 2001.06d
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• pp.45-48
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• 2001

Unequal Error Protection(UP) is reasonable scheme in transmission of compressed video with low bit rate. Because it offers the error correction ability each other data according to the Source Significance Information. Hence it can also be flexible to the given channel environment on the video transmission. This paper propose the joint source channel coding through the UEP in consideration of the hierarchical structure of H.263+ based video and the influence of the transmission error. It especially proposes the error-resilient video transmission technique which can reduce complexity of channel coder & decoder by partitioning the video data with a frame. As the result of the proposed algorithm, it is possible to increase the quality of reconstructed video in the error environment without creating additional bits.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.263-266
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• 2009

When video packets are transmitted over error-prone networks, the leaky prediction can be used to mitigate the effect of error propagation. The leaky factor provides trade-off between coding efficiency and error resilience in the leaky prediction. In this paper, we propose an improved leaky prediction method where the leaky factor is adaptively determined for each frame by minimizing the estimated end-to-end distortion at the encoder. Experimental results show that the proposed method with the adaptive leaky factor shows the better performance of the error robustness as compared with the conventional method.

• Broadcasting and Media Magazine
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• v.7 no.3
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• pp.94-103
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• 2002

본 논문은 전송 오류가 존재하는 환경에서 사용될 수 있는 오류 내성을 갖는 비트스트림을 생성하기 위한 H.26L부호화 알고리즘을 소개한다. 소개되는 새로운 부호화 알고리즘은 기존의 GOB 단위 forced intra-refreshment 기법이나 multiple decoder simulation 기반 RD 최적화 기법에 비해서 RD 특성 등에서 대단히 우수한 성능을 보인다.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.6
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• pp.736-745
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• 2002

In network delivery of compressed video, packets may be lost if the channel is unreliable like Internet. Such losses tend to of cur in burst like continuous bit-stream error. In this paper, we propose an effective error-concealment approach to which an error resilient video encoding approach is applied against burst errors and which reduces a complexity of error concealment at the decoder using data hiding. To improve the performance of error concealment, a temporal and spatial error resilient video encoding approach at encoder is developed to be robust against burst errors. For spatial area of error concealment, block shuffling scheme is introduced to isolate erroneous blocks caused by packet losses. For temporal area of error concealment, we embed parity bits in content data for motion vectors between intra frames or continuous inter frames and recovery loss packet with it at decoder after transmission While error concealment is performed on error blocks of video data at decoder, it is computationally costly to interpolate error video block using neighboring information. So, in this paper, a set of feature are extracted at the encoder and embedded imperceptibly into the original media. If some part of the media data is damaged during transmission, the embedded features can be extracted and used for recovery of lost data with bi-direction interpolation. The use of data hiding leads to reduced complexity at the decoder. Experimental results suggest that our approach can achieve a reasonable quality for packet loss up to 30% over a wide range of video materials.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.7A
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• pp.1028-1036
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• 2000

In this paper, an error-resilient image compression technique using wavelet transform is proposed. The zerotree technique that uses properties of statistics, energy and directions of wavelet coefficients in the space-frequency domain shows effective compression results. Since it is highly sensitive to the propagation of channel errors, evena single bit error degrades the whole image quality severely. In the proposed algorithm, the image is encoded by the SPIHT(Set Partitioning in Hierarchical Trees) algorithm using the zerotree coding technique. Encoded bitstreams are partitioned into some blocks using the subband correlations and then fixed-length blocks are made by using the effective bit reorganization algorithm. finally, an effective bit allocation technique is used to limit error propagation in each block. Therefore, in low BER the proposed algorithm shows similar compression performance to the zerotree compression technique and in high BER it shows better performance in terms of PSNR than the conventional methods.

• 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