• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.1
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• pp.23-30
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• 2010

The H.264/AVC is increasingly used in broadcast video applications such as Internet Protocol television (IPTV), digital multimedia broadcasting (DMB) because of high compression performance. But the H.264/AVC coded video can be delivered to the widespread end-user equipment for MPEG-2 after transcoding between this video standards. This paper suggests a new transcoding algorithm for H.264/AVC to MPEG-2 transcoder that uses motion vector clustering in order to reduce the complexity without loss of video quality. The proposed method is exploiting the motion information gathered during h.264 decoding stage. To reduce the search space for the MPEG-2 motion estimation, the predictive motion vector is selected with a least distortion of the candidated motion vectors. These candidate motion vectors are considering the correlation of direction and distance of motion vectors of variable blocks in H.264/AVC. And then the best predictive motion vector is refined with full-search in ${\pm}2$ pixel search area. Compared with a cascaded decoder-encoder, the proposed transcoder achieves computational complexity savings up to 64% with a similar PSNR at the constant bitrate(CBR).

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.162-164
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• 2010

H.264/AVC(Advanced Video Coding) is a standard for video compression. H.264/AVC provides good video quality at substantially lower bit rates than previous standards. In this papers, we propose the efficient architecture of H.264/AVC decoder using GPGPU. GPGPU can process many of operation in parallel. IQ/IDCT is possible that parallel processing in H.264/AVC decoding algorithm.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.2
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• pp.50-57
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• 2010

In this paper, we address H.264/AVC video transmission using multiple antennaed phycical layer. When multiple antennas are used, the signals from the other antennas are interferences from the perspective of a target antenna, resulting in lowered video quality. In an effort to improve the video quality, in this paper, we propose a novel detection ordering scheme. We conduct computer simulations to show the efficacy of the proposed scheme.

• Journal of the Semiconductor & Display Technology
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• v.14 no.1
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• pp.51-53
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• 2015

H.264/AVC is international video coding standard, which shows improved code and efficiency than the existing video standards. H.264/AVC proposes data partitioning method that considerably to be an effective layering technique which separates important addressing data from the residual data. UEP(Unequal Error Protection) turbo code of H.264/AVC uses retransmission system to get the UEP effectively. However, Data partitioning system of H.264/AVC is inefficient method in turbo code of H.264/AVC. Based on this observation, we propose the new UEP turbo code algorithm that reconstructs input sequence of turbo code without retransmission system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.11
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• pp.2020-2025
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• 2006

H.264/AVC is newest video coding standard of the ITU-T Video coding Experts Group and the ISO/IEC Moving Picture Expets Group. Recently H.264/AVC has been adopted as a video compression standard in DMB and multimedia equipments. In this paper, we propose a H.264/AVC intra frame decoder which can minimize the memory usage and chip size. The proposed intra frame decoder is described in VHDL language and simulated in model_sim. It was verified in chip level by downloading to XCV1000E FPGA chip.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.2
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• pp.46-52
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• 2011

This paper presents adaptive spread-spectrum watermarking scheme on the H.264/AVC video. The H.264/AVC has become popular video coding since it's compression performance has been improved greatly. That is why there is not enough space for embedding watermark using the spread-spectrum method. To overcome this problem, we propose selective block embedding scheme. The blocks which don't contain non-zero DCT (Discrete Cosine Transform) coefficients are selected by value. So we have enough space to embed watermarks. Experimental result shows that proposed scheme improves recovery rates of watermark about 12% and reduces distortion of watermarked video.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1104-1114
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• 2007

Digital video compression technique has played an important role that enables efficient transmission and storage of multimedia data where bandwidth and storage space are limited. The new video coding standard, H.264/AVC, developed by Joint Video Team(JVT) significantly outperforms previous standards in compression performance. Especially, variable length code(VLC) plays a crucial pun in video and image compression applications. H.264/AVC standard adopted Context-based Adaptive Variable Length Coding(CAVLC) as the entropy coding method. CAVLC of H.264/AVC requires a large number of the memory accesses. This is a serious problem for applications such as DMB and video phone service because of the considerable amount of power that is consumed in accessing the memory. In order to overcome this problem in this paper, we propose a variable length technique that implements memory-free coeff_token, level, and run_before decoding based on arithmetic operations and using only 70% of the required memory at total_zero variable length decoding.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.6 s.312
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• pp.97-104
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• 2006

The state-of-the-art H.264/AVC standard was designed for the lossy video coding so that it could not yield the best performance for lossless video coding. In this paper, we propose two efficient intra lossless coding methods by embedding a pixel-wise prediction into the H.264/AVC. One is based on the pixel-wise prediction for the residual signal of the H.264/AVC intra Prediction and the other suggests a newly additional intra prediction mode for the conventional intra prediction. We found that the proposed lossless coding algorithms could achieve approximately $12%{\sim}25%$ more bit saving compared to the H.264/AVC FRExt high profile for several test sequences in terms of a compression ratio.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.5 s.311
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• pp.72-78
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• 2006

In this paper, we present a video shot retrieval algorithm in H.264/AVC compression domain. Unlike previous standards such as MPEG-2 and 4, H.264/AVC supports a variable block size for motion compensation. Therefore, existing video retrieval algorithms exploiting the motion vectors in MPEG-2 and 4 domains are not appropriate for H.264/AVC. So, we devise a method to project motion vectors with larger than $4{\times}4$ block sizes into those for the smallest $4{\times}4$ blocks. It also uses correlations among features for the measure of similarity. Experimental results with standard videos of 10558 frames and commercial videos of 48161 frames show that the proposed method yields ANMRR less than 0.2.

• Journal of Broadcast Engineering
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• v.10 no.4 s.29
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• pp.515-527
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• 2005

A next-generation codec should be developed to be a scalable video codec(SVC) that not only maximizes the coding efficiency but also adaptively copes with the various communication devices and the variation of network environments. To meet these requirements, Joint Video Team (JVT) of ISO/IEC and ITU-T is standardizing H.264/AVC based SVC. In this paper, we introduce research directions and status on SVC standardization and also analyze techniques and algorithms adopted in the current SVC.