• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.123-130
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• 2004

In this paper, an advanced error tracking algorithm by using feedback channel was proposed for error resilient transmission. Using this proposed algorithm, the propagation of errors were reduced within the decoded data over bit error prone network. The addresses of corrupted blocks are reported to encoder by decoder. With negative acknowledgments of feedback channel, the encoder can precisely calculate negative acknowledgments and track the propagated errors by examining the backward motion dependency for proper pixel in the current encoding frame. The error-propagation effects can be terminated completely by INTRA refreshing the affected macro-blocks by using proposed error tracking algorithm. By utilizing the selective four-corner error tracking approximation, the error tracking computations of the proposed algorithm is less than that of the algorithm using full pixel without substantial degradation in video quality. The proposed algorithm can track errors rapidly and accurately.

• Journal of information and communication convergence engineering
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• v.19 no.3
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• pp.175-179
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• 2021

Enhancing the reliability of the system is important for recent system-on-chip (SoC) designs. This importance has led to studies on fault diagnosis and tolerance. Fault-injection (FI) techniques are widely used to measure the fault-tolerance capabilities of resilient systems. FI techniques suffer from limitations in relation to environmental conditions and system features. Moreover, a hardware-based FI can cause permanent damage to the target system, because the actual circuit cannot be restored. Accordingly, we propose a simulation-based FI framework based on the Verilog Procedural Interface for measuring the failure rates of SoCs caused by soft errors. We execute five benchmark programs using an ARM Cortex M0 processor and inject soft errors using the proposed framework. The experiment has a 95% confidence level with a ±2.53% error, and confirms the reliability and feasibility of using proposed framework for fault analysis in SoCs.

• 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.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.1
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• pp.62-77
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• 2010

Emerging applications with high data rates will need to transport bulk data reliably in wireless sensor networks. ARQ (Automatic Repeat request) or Forward Error Correction (FEC) code schemes can be used to provide reliable transmission in a sensor network. However, the naive ARQ approach drops the whole frame, even though there is a bit error in the frame and the FEC at the bit level scheme may require a highly complex method to adjust the amount of FEC redundancy. We propose a bulk data transmission scheme based on erasure-resilient code in this paper to overcome these inefficiencies. The sender fragments bulk data into many small blocks, encodes the blocks with LT codes and packages several such blocks into a frame. The receiver only drops the corrupted blocks (compared to the entire frame) and the original data can be reconstructed if sufficient error-free blocks are received. An incidental benefit is that the frame error rate (FER) becomes irrelevant to frame size (error recovery). A frame can therefore be sufficiently large to provide high utilization of the wireless channel bandwidth without sacrificing the effectiveness of error recovery. The scheme has been implemented as a new data link layer in TinyOS, and evaluated through experiments in a testbed of Zigbex motes. Results show single hop transmission throughput can be improved by at least 20% under typical wireless channel conditions. It also reduces the transmission time of a reasonable range of size files by more than 30%, compared to a frame ARQ scheme. The total number of bytes sent by all nodes in the multi-hop communication is reduced by more than 60% compared to the frame ARQ scheme.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.303-310
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• 2007

Compressed video bitstreams are intended for real-time transmission over communication networks. Because video compression algorithms eliminate the temporal, spatial, and statistical redundancies, the coded video bitstreams are very sensitive to transmission errors. We propose an error resilient video coding technique to limit the effect of error propagation in low bit-rate video coding. The success of error resilient coding techniques relies on how accurately the transmission errors can be detected. To detect the transmission error, we propose a very simple error detection technique based on data hiding Next, we conceal the corrupted MB data using intra MB refresh and motion compensation with the estimated motion vector and compare the simulation results. This method will be useful in video communication in error Prone environment such as WCDMA networks.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1721-1730
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• 1999

In this thesis, an error resilient video coding algorithm, under the error-prone environment such as wireless communication, is suggested. The suggested algorithm adapts the Classified VQ method for intra imagers that reduces some load by searching similar vectors. The Duplicate Vector Position Code is proposed for the higher compression efficiency and the robust decoding in error environment. As a result, the bitstream encoded by the proposed method is in a CBR(Constant Bit Rate) preventing from error propagation. The experiment that adds practical error to the encoded bitsrteam shows the error-robustness superior to H.263.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.4
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• pp.108-115
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• 2009

In this paper, we propose a novel true-motion estimation technique supporting efficient frame error concealment for error-resilient video coding. In general, it is important to accurately obtain the true-motion of objects in video sequences for effectively recovering the corrupted frame due to transmission errors. However, the conventional motion estimation (ME) technique, which minimizes a sum of absolute different (SAD) between pixels of the current block and the motion-compensated block, does not always reflect the true-movement of objects. To solve this problem, we introduce a new metric called an absolute difference of motion vectors (ADMV) which is the distance between motion vectors of the current block and its motion-compensated block. The proposed ME method can prevent unreliable motion vectors by minimizing the weighted combination of SAD and ADMV. In addition, the proposed ME method can significantly improve the performance of error concealment at the decoder since error concealment using the ADMV can effectively recover the missing motion vector without any information of the lost frame. Experimental results show that the proposed method provides similar coding efficiency to the conventional ME method and outperforms the existing error-resilient method.

• The Magazine of Kiice
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• v.2 no.1
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• pp.44-50
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• 2001

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.39 no.6
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• pp.602-611
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• 2002

Recent advances in technology have resulted in rapid growth in mobile communication. With this explosive growth, reliable transmission and error resilient technique become increasingly necessary to offer high quality multimedia service. The success of error resilient techniques at decoder sensitively depends on error detection performance. Therefore, this paper proposes a computationally very simple and efficient error detection technique using fragile watermark for real-time video communication. To balance between image quality degradation and error detection efficiency, fragile watermark is embedded only in least significant bits of selected transform coefficients. The proposed method is workable without additional bit in video bitstream and can be implemented very efficiently. This method will be useful in video communication in error prone environment such as wireless channel.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.189-196
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• 2003

This paper describes an error resilient video data transmission method using information hiding. In order to localize transmission errors in receiver, video encoder embeds one bit for a macro block during encoding process. Embedded information is detected during decoding process in the receiver, and the transmission errors can be localized by comparing the original embedding data. The localized transmission errors can be easily corrected, thus the degradation in a reconstructed image can be alleviated. Futhermore, the embedded information can be applied to protect intellectual property rights of the video data. Experimental results for 3 QCIF sized video sequenced composed of 150 frames respectively show that, while degradation in video streams in which the information is embedded is negligible, especially in a noisy channel, the average PSNR of reconstructed images can be improved about 5 dB by using embedded information. Also, intellectual property rights information can be effectively obtained from reconstructed images.