• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.3
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• pp.129-137
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• 2007

MPEG-4 FGS is one of scalable video coding schemes specified In ISO/IEC 14496-2 Amendment 2, and particularly standardized as a scheme for providing fine granular quality and temporal scalabilities. In this paper, we propose a sign-bit reduction technique in embedded bit-plane coding to enhance the coding efficiency of MPEG-4 FGS system. The general structure of the FGS system for the proposed scheme is based on the standard MPEG-4 FGS system. The proposed FGS enhancement-layer encoder takes as input the difference between the original DCT coefficient and the decision level of the quantizer instead of the difference between the original DCT coefficient and its reconstruction level. By this approach, the sign information of the enhancement-layer DCT coefficients can be the same as that of the base-layer ones at the same frequency index in DCT domain. Thus, overhead bits required for coding a lot of sign information of the enhancement-layer DCT coefficients in embedded bit-plane coding can be removed from the generated bitstream. It is shown by simulations that the proposed FGS coding system provides better coding performance, compared to the MPEG-4 FGS system in terms of compression efficiency.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.3 s.303
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• pp.31-40
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• 2005

In this paper, we develop an approach toward JSC(Joint Source-Channel Coding) method for MPEG-4 based FGS(Fine Granular Scalability) video coding and transmission in fixed and mobile receiving environment(Digital Audio Broadcasting, DAB). The source coder used MPEG-4 FGS video codec, the channel coder used RCPC(Rate Compatible Punctured Convolution) code and the modulation method used QPSK modulation. We have considered channel environment of AWGN and mobile receiving environment. This study determined optimum Trade-off point between source bit rate and channel coding rate in variable channel states. We compared FGS-JSC method and general single layer CBR(Constant Bit Rate) transmission. In this results, FGS-JSC was appeared better performance than CBR transmission.

• The KIPS Transactions:PartB
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• v.18B no.5
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• pp.249-254
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• 2011

FGS (fine granularity scalability) supporting scalability in MPEG-4 Part 2 is a scalable video coding scheme that provides bit-rate adaptation to varying network bandwidth thereby achieving of its optimal video quality. In this paper, we proposed FGS coding scheme which performs one more bit-plane coding for residue signal occured in the enhancement-layer of the basic FGS coding scheme. The experiment evaluated in terms of video quality scalability of the proposed FGS coding scheme by comparing with FGS coding scheme of the MPEG-4 verification model (VM-FGS). The comparison was conducted by analysis of PSNR values of three tested video sequences. The results showed that when using rate control algorithm VM5+, the proposed FGS coding scheme obtained Y, U, V PSNR of 0.4 dB, 9.4 dB, 9 dB averagely higher and when using fixed QP value 17, obtained Y, U, V PSNR of 4.61 dB, 20.21 dB, 16.56 dB averagely higher than the existing VM-FGS. From results, we found that the proposed FGS coding scheme has higher video quality scalability to be able to achieve video quality from minimum to maximum than VM-FGS.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2005.11a
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• pp.177-180
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• 2005

MPEG-4 FGS 비트 스트림을 서버측에서는 각 클라이언트의 채널환경에 맞게 적절한 비트율로 추출하여 각 클라이언트에게 전송해야 한다. 부분적인 비트 스트림만으로도 영상 복원이 가능하지만, 같은 비트율에서 전송화질의 극대화를 위해서는 비트 스트림의 추출방법에 대한 연구가 필요하다. 이에 본 논문은 MPEG4 FGS 비디오 스트림을 네트워크 상에서 동적인 통신용량의 변화에 맞춰 적절한 비트율로 추출하는 방법에 대해 제안한다. 제안하는 방법은 같은 비트율에서 전송화질의 극대화를 위해 향상계층의 각 비트 평면(bit-plane)이 손실됐을 때 품질에 미치는 영향을 고려하여 비트율을 줄인다. 이렇게 함으로써 동일한 비트율이 주어진 경우 얻을 수 있는 종단간(end-to-end) 비디오 품질의 향상을 비교 분석하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.7A
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• pp.711-723
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• 2002

A finer granular scalable (FGS) version of ISO/IEC MPEG-4 video streaming is investigated in this work with the prioritized stream delivery over loss-rate differentiated networks. Our proposed system is focused on the seamless integration of rate adaptation, prioritized packetization, and simplified differentiation for the MPEG-4 FGS video streaming. The proposed system consists of three key components: 1) rate adaptation with scalable source encoding, 2) content-aware prioritized packetization, and 3) loss-based differential forwarding. More specifically, a constant-quality rate adaptation is first achieved by optimally truncating the over-coded FGS stream based on the embedding rate-distortion (R-D) information (obtained from a piecewise linear R-D model). The rate-controlled video stream is then packetized and prioritized according to the loss impact of each packet. Prioritized packets are transmitted over the underlying network, where packets are subject to differentiated dropping and forwarding. By focusing on the end-to-end quality, we establish an effective working conditions for the proposed video streaming and the superior performance is verified by simulated MPEG-4 FGS video streaming.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.175-178
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• 2008

MPEG-4 Part 2 에서 표준으로 채택된 FGS (fine granularity scalability) 코딩 기법은 전송 선로의 상태가 급변하는 경우에도 주어진 대역폭에서 최적의 화질 향상을 얻을 수 있도록 설계된 망 상태에 적응적인 스케일러블 비디오 코딩 기법이다 [1][2][9]. 본 논문에서는 기존의 FGS 향상 계층에서 영상의 잔여 신호를 다시 한 번 bit-plane 코딩을 해줌으로써 화질 확장성을 더 높인 Advanced FGS 코딩 구조를 제안하였다. 본 논문의 실험에서는 기존의 MPEG-4 VM (verification model)에서 사용된 FGS 코딩과의 비교를 통해 Advanced FGS 구조의 화질 확장성을 평가하였다. 비교는 두 부호화 기술의 PSNR 값의 분석으로 이루어졌고, 결과를 통해 Advanced FGS 구조가 고화질을 가지며, 화질 확장성이 더 높은 구조임을 알 수 있었다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04a
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• pp.795-798
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• 2002

본 논문에서는 MPEG-4 표준에서 채택된 FGS(Fine Granualrity Scalability)를 이용한 계층적 비디오 부호화 방법을 적용하였다. MPEG-4 FGS는 인터넷에서 이용되는 다양한 특성의 단말기들과 대역폭 변통에서 유연성 있는 기술이다. 적용된 MPEG-4 FGS 기술은 DCT 기반 비트 평면 부호화를 이용한다. 실험에서는 일반적인 SNR 계층 비디오 코딩(Multi-layered SNR scalable video coding)과의 비교를 통해 FGS의 효율성을 평가한다. 비교는 두 부호화 기술의 PSNR 값의 분석을 가지고 이루어졌고 MPEG-4 FGS 기술이 이전의 다층 SNR계층 비디오 부호화 방법보다 평균 $1\sim2dB$ 정도의 높은 값으로 나타났다. 이를 동해 MPEG-4 FGS가 효율성면에서 다층 SNR계층 비디오 부호화 방법보다 우수함을 알 수 있지만, 단일 계층부호화(Single-layered scalable video coding)에 비해서는 효율성이 낮게 나타났다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.783-786
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• 2002

멀티미디어 컨텐트의 실시간 전송은 인터넷에서 중요한 기술영역으로 나타나고 있다. 본 논문에서는 MPEG-4 표준에서 채택된 FGS(Fine Granualrity Scalability)를 이용한 계층적 비디오 부호화 방법의 효율성 향상을 위한 방법을 제시하였다. MPEG-4 FGS는 인터넷에서 이용되는 다양한 특성의 단말기들과 대역폭 변동에서 유연성 있는 기술이다. 일반적인 계층 비디오 부호화 기법보다 PSNR값이 평균 1$\sim$2dB정도 높게 나타난다. 그러나 단일 계층 부호화 방법에 비해서는 효율성이 낮게 나타난다. 제안된 방법에서는 이런 FGS의 효율성을 높이기 위한 방법으로 시간 스케일러빌리티를 갖는 FGST(FGS temporal scalability)층을 적용하였다. 기본계층은 일반적인 FGS 부호화에 의해 이루어지고 상위계층 부호화로 시간적 스케일러빌리티를 갖는 FGST를 이용한다. 실험은 프레임율 10 fbs의 container와 mobile 영상에 대해 이루어졌고 두 영상 모두에 대해 FGS 부호화만을 적용하는 경우보다 상위계층으로서 FGST를 이용하는 경우 상당한 효율성 향상이 있음을 보인다.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.3
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• pp.91-96
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• 2008

An image scalablity function is noted as technology to embody One Source-Multi-use's Image division by the network Bandwidth and diversification of resolution of reception terminal recently. In MPEG present H.264/MPEG-4 AVC that do to standardization of SVC (Scalable Video Coding) that know go and SVC can offer space time SNR scalability. But, encoding that do scalable usually is known that encoding efficiency drops than encoding that do rain scalable during time and treatise that see. Examine technique to plan improvement of management quality as that aim to time, SNR scalability in treatise that see so and change FGS (Fine Granular Scalability) function that offer SNR scalability that do about scalability's particle size and encoding efficiency relation by SVC to foundation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.6C
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• pp.634-647
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• 2003

In MPEG-4 FGS (fine granular scalability) video, SE (selective enhancement) function is adopted to enhance the subject quality of the region of interest (ROI). However, it has the problem of excessive bit-rate increase in the enhancement layer. We present a new rectangular region-based SE (RSE) algorithm to significantly reduce the overhead bits resulting from the standard SE. The proposed RSE is based on two new algorithms. The first is to apply the SE function to a rectangular region. By doing so, we can reduce the required bits for describing the selectively enhanced region. The second is to use constrained bit-plane scanning (CBS) to encode bit-planes of the enhancement layer. By using CBS, we can efficiently encode the ALL-ZERO symbols that are generated by applying the SE. It Is shown by simulation that the proposed RSE can provide a good visual quality for the selected rectangular region with significantly reduced overhead bits.