• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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• pp.225-227
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• 2009

International standard specification, H.264/SVC improved from H.264/AVC, is set up so as to promote free use of huge multimedia data in various channel environments.;H.264/AVC is a international standard speicification for video compression, adopted and commercialized as standard for DMB broadcasting by JVT of ISO/IEC MPEG and ITU-T VCEG. SVC standard uses 'intra/inter prediction' in AVC as well as 'inter-layer intra prediction', 'inter-layer motion prediction' and 'inter-layer residual prediction' to improve efficiency of encoding. Among prediction technologies, 'inter-layer intra prediction' is to use co-located block of up sampled sublevels as a prediction signal. At this time, application of interpolation is one of the most important factors to determine encoding efficiency. SVC's currently using poly-phase FIR filter of 4-tap and 2-tap respectively to luma components. This paper is written for the purpose of analyzing encoding performance according to the interpolation. For this purpose, we applied poly-phase FIR filter of '2-tap', '4-tap' and '6-tap' respectively to luma components and then measured bit-rate, PNSR and running time of interpolation filter. We're expecting that the analysis results of this paper will be utilized for effective application of interpolation filter. SVC standard uses 'intra/inter prediction' in AVC as well as 'inter-layer intra prediction', 'inter-layer motion prediction' and 'inter-layer residual prediction' to improve efficiency of encoding.

• ETRI Journal
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• 제35권6호
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• pp.990-1000
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• 2013

This paper describes the scalable extension of High Efficiency Video Coding (HEVC) to provide flexible high-quality digital video content services. The proposed scalable codec is designed on multi-loop decoding architecture to support inter-layer sample prediction and inter-layer motion parameter prediction. Inter-layer sample prediction is enabled by inserting the reconstructed picture of the reference layer (RL) into the decoded picture buffer of the enhancement layer (EL). To reduce the motion parameter redundancies between layers, the motion parameter of the RL is used as one of the candidates in merge mode and motion vector prediction in the EL. The proposed scalable extension can support scalabilities with minimum changes to the HEVC and provide average Bj${\o}$ntegaard delta bitrate gains of about 24% for spatial scalability and of about 21% for SNR scalability compared to simulcast coding with HEVC.

• ETRI Journal
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• 제32권4호
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• pp.577-587
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• 2010

The layered coding structure of scalable video coding (SVC) with adaptive inter-layer prediction causes noticeable computational complexity increments when compared to existing video coding standards. To lighten the computational complexity of SVC, we present a fast algorithm to speed up the inter-mode decision process. The proposed algorithm terminates inter-mode decision early in the enhancement layers by estimating the rate-distortion (RD) cost from the macroblocks of the base layer and the enhancement layer in temporal, spatial, and inter-layer directions. Moreover, a search range decision algorithm is also proposed in this paper to further increase the motion estimation speed by using the motion vector information from temporal, spatial, or inter-layer domains. Simulation results show that the proposed algorithm can determine the best mode and provide more efficient total coding time saving with very slight RD performance degradation for spatial and quality scalabilities.

• IEIE Transactions on Smart Processing and Computing
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• 제4권6호
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• pp.434-442
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• 2015

In this paper, we propose an integrated spatial and view scalable video codec based on high efficiency video coding (HEVC). The proposed video codec is developed based on similarity and uniqueness between the scalable extension and 3D multi-view extension of HEVC. To improve compression efficiency using the proposed scalable multi-view video codec, inter-layer and inter-view predictions are jointly employed by using high-level syntaxes that are defined to identify view and layer information. For the inter-view and inter-layer predictions, a decoded picture buffer (DPB) management algorithm is also proposed. The inter-view and inter-layer motion predictions are integrated into a consolidated prediction by harmonizing with the temporal motion prediction of HEVC. We found that the proposed scalable multi-view codec achieves bitrate reduction of 36.1%, 31.6% and 15.8% on the top of ${\times}2$, ${\times}1.5$ parallel scalable codec and parallel multi-view codec, respectively.

• 방송공학회논문지
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• 제12권4호
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• pp.360-372
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• 2007

본 논문에서는 MPEG-4 제10부 규격인 Advanced Video Coding의 제 3 개정 규격 (MPEG-4 Part 10 Amendment 3)으로서 현재 표준화가 진행 중인 Scalable Video Coding (SVC) 규격에 대해 기본 계층에서 예측한 움직임 벡터 정보를 이용하여 향상 계층에서 모드 결정을 고속화하는 방법에 대해 소개한다. 본 논문에서 제안된 방법은 공간 계위성을 갖는 비디오를 부호화하는데 있어서 기본 계층에서 예측한 블록모드 중에서 큰 블록인 $16{\times}16$ 블록에서 움직임 벡터가 (0, 0)일 경우 또는 하위 계층의 정보를 이용하여 얻은 움직임 보상 블록과 향상 계층의 현재 블록의 잔차 신호의 정수변환의 계수가 모두 0인 경우에 대하여 향상 계층에서는 $16{\times}16$ 블록에 대해서만 율-왜곡 최적화를 수행함으로써 향상 계층에서 움직임 모드 결정을 조기에 완료하게 하여 공간 계위성 부호화를 고속화하거나 위 두 경우가 아닌 경우에는 후보 모드의 수를 감소시켜 감소된 모드에 대해서만 율-왜곡 최적화를 수행하는 방법을 제시한다. 이 제안 방법을 이용하였을 경우 향상 계층에의 모드 결정과정을 고속화함으로써 전체 스케일러블 비디오 부호화기의 연산량 및 복잡도를 전체 부호화 소요 시간 대비 최대 72%까지 감소시켰다. 그러나 연산량 감소에 따른 비트율의 증가와 화질 열화는 각각 최대 1.73%와 최대 0.25dB로 무시할 수 있을 정도로 작음을 확인하였다.

• 대한임베디드공학회논문지
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• 제9권2호
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• pp.81-86
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• 2014

In the scalable video coding standard, inter-layer prediction based on the coding information of the base layer was adopted to increase the coding performance. This prediction tool results in new syntax elements called motion_prediction_flag (mPF) and residul_prediction_flag(rPF), which are carried to notify the motion vector predictor (MVP) and reference block required in the motion compensation of the decoder. In this paper, an efficient coding method for mPF is proposed to enhance coding efficiency of the salable video coding standard. Through an analysis on the transmission of mPF based on the relationship between the MVPs, we discover the conditions where mPF is unnecessary at the decoder and suggest a modified rate-distortion (RD) cost function to make RD optimization more effective. Simulation results show that the proposed method offers BD rate savings of approximately 1.4%, compared with the conventional SVC standard.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.189-191
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• 2005

In the scalable extension of H.264/AVC, the codec is based on a layered approach to enable spatial scalability. In each layer, the basic concepts of motion compensated prediction and intra prediction are employed as in standard H.264/AVC. Additionally inter-layer prediction algorithm between successive spatial layers is applied to remove redundancy. In the inter-layer prediction, as the prediction we can use the signal that is the upsampled signal of the lower resolution layer. In this case, coding efficiency can be variable as the kinds of interpolation filter. In this paper, we investigate the approach to select the interpolation filter for residual signal in order to optimal prediction.

• 방송공학회논문지
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• 제26권5호
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• pp.652-655
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• 2021

Versatile Video Coding(VVC)의 압축 효율을 끌어올리기 위하여 다양한 화면 간 예측(inter prediction)기법 중 적응적 움직임 벡터 해상도(Adaptive motion vector resolution, 이하 AMVR)기술이 채택되어 왔다. 다만, AMVR을 적용하여 최적의 해상도를 결정하기 위해서는 매 부호화 유닛마다 다양한 테스트를 진행해야 하며, 이는 율-왜곡 비용의 계산 복잡도 증가를 야기한다. 따라서 VVC의 부호화 복잡도의 감소를 위해 효과적으로 최적의 AMVR 모드를 찾아야 한다. 본 논문에서는 보다 다양한 데이터셋 기반 하에 경량화된 신경망 기반의 AMVR 결정 알고리즘을 제안한다.

• IEIE Transactions on Smart Processing and Computing
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• 제2권6호
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• pp.345-349
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• 2013

This paper proposes a simplified generalized residual prediction (GRP) that reduces the computational complexity of spatial scalability in scalable high efficiency video coding (SHVC). GRP is a coding tool to improve the inter prediction by adding a residual signal to the inter predictor. The residual signal was created by carrying out motion compensation (MC) of both the enhancement layer (EL) and up-sampled reference layer (RL) with the motion vector (MV) of the EL. In the MC process, interpolation of the EL and the up-sampled RL are required when the MV of the EL has sub-pel accuracy. Because the up-sampled RL has few high frequency components, interpolation of the up-sampled RL does not give significantly new information. Therefore, the proposed method reduces the computational complexity of the GRP by skipping the interpolation of the up-sampled RL. The experiment on SHVC software (SHM-2.0) showed that the proposed method reduces the decoding time by 10 % compared to conventional GRP. The BD-rate loss of the proposed method was as low as 1.0% on the top of SHM-2.0.

• ETRI Journal
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• 제29권3호
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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.