We propose an extended packetization-aware mapping algorithm based on fountain codes to enhance video stream performance which is vulnerable to packet *** properly utilizing the proposed algorithm in finite-length cas...
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We propose an extended packetization-aware mapping algorithm based on fountain codes to enhance video stream performance which is vulnerable to packet *** properly utilizing the proposed algorithm in finite-length cases,the edges connecting to a source symbol are scattered over multiple encoding packets so that the decoding probabilities are ***,an improved degree distribution is designed to obtain better decoding *** results,it is confirmed that the proposed algorithm in finite-length cases can augment decoding probabilities and the improved degree distribution can increase peak signal-to-noise ratio(PSNR) of scalable video coding(SVC) in a hostile communication environment.
A novel frame-level rate control (RC) algorithm is presented in this paper for temporal scalability of scalable video coding. First, by introducing a linear quality dependency model, the quality dependency between a c...
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A novel frame-level rate control (RC) algorithm is presented in this paper for temporal scalability of scalable video coding. First, by introducing a linear quality dependency model, the quality dependency between a coding frame and its references is investigated for the hierarchical B-picture prediction structure. Second, linear rate-quantization (R-Q) and distortionquantization (D-Q) models are introduced based on different characteristics of temporal layers. Third, according to the proposed quality dependency model and R-Q and D-Q models for each temporal layer, adaptive weighting factors are derived to allocate bits efficiently among temporal layers. Experimental results on not only traditional quarter common intermediate format/common intermediate format but also standard definition and high definition sequences demonstrate that the proposed algorithm achieves excellent coding efficiency as compared to other benchmark RC schemes.
scalable video coding incorporated with computation-aware ability achieves quality as well as being computation scalable. This paper presents a computation-aware algorithm for scalable video coding with spatial/qualit...
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scalable video coding incorporated with computation-aware ability achieves quality as well as being computation scalable. This paper presents a computation-aware algorithm for scalable video coding with spatial/quality scalability aiming for the best trade-off between rate distortion performance and computational consumption. We first observe and analyze and then establish a model for the motion vector difference relationship between the scalable base and enhancement layers. By using the modeling results, a linear algorithm for computation distribution is thus proposed to allocate the computation for each macroblock in the enhancement layer. In addition, the rate distortion costs of the base layer are also taken into account for the computation allocation process in order to further improve the coding performance. The simulation results demonstrate that our proposed computation-aware algorithm not only accomplishes better rate distortion performance than other works under the same computational constraints, but also achieves less computation necessities. (C) 2015 Elsevier Inc. All rights reserved.
Selective protection can exploit dependency coding properties to effectively perform partial protection on scalable video coding (SVC) bitstreams since protecting frames in lower scalability layers affects visual qual...
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Selective protection can exploit dependency coding properties to effectively perform partial protection on scalable video coding (SVC) bitstreams since protecting frames in lower scalability layers affects visual quality of the reconstructed frames in higher scalability layers. In this paper, we propose a selective protection scheme that maximizes protection effects by the minimum number of encoded frames to be protected in the SVC bitstream domain. We first model the SVC dependency coding structure as a directed acyclic graph which is characterized with an estimated visual quality value as the attribute at each node. In addition, a visual quality estimation model is proposed based on the proportions of intra-predicted and inter-predicted MBs, amounts of residues, and estimated visual quality of reference frames. The proposed selective protection scheme traverses the dependency graph to find optimal protection paths that can give the maximum visual quality degradation. Experimental results show that, compared to the existing protection schemes, the proposed selective protection scheme reduces computation complexity in the number of protected frames, the amount of protected data, and the protection time saving. The SVC file format specification supports the carriage of selectively protected bitstreams based on the concept of our selective protection in dependency coding structure of SVC.
The newest videocoding standard called scalable video coding (SVC) provides broad applications in multimedia communications. SVC encoder consumes great computational complexity when compared to previous videocoding ...
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The newest videocoding standard called scalable video coding (SVC) provides broad applications in multimedia communications. SVC encoder consumes great computational complexity when compared to previous videocoding standards. This paper presents a fast mode decision algorithm that speeds up the SVC encoding process through probabilistic analysis. The mode of the enhancement layer is. first predicted by statistical analysis. Afterward, Bayesian theorem is utilized to detect whether the prediction mode of the current macroblock is the best or not. The mode is further predicted and refined by the Markov process. Experimental results show that the proposed algorithm significantly reduces computational complexity with negligible peak signal-to-noise ratio degradation and bitrate increase in the enhancement layers.
Although scalable video coding can achieve coding efficiencies comparable with single layer videocoding, its computational complexity is higher due to its additional inter-layer prediction process. This paper present...
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Although scalable video coding can achieve coding efficiencies comparable with single layer videocoding, its computational complexity is higher due to its additional inter-layer prediction process. This paper presents a fast adaptive termination algorithm for mode selection to increase its computation speed while attempting to maintain its coding efficiency. The developed algorithm consists of the following three main steps which are applied not only to the enhancement layer but also to the base layer: a prediction step based on neighboring macroblocks, a first round check step, and a second round check step or refinement if failure occurs during the first round check. Comparison results with the existing algorithms are provided. The results obtained on various video sequences show that the introduced algorithm achieves about one-third reduction in the computation speed while generating more or less the same video quality.
In this paper, we propose a new efficient entropy coding scheme, namely context-based binary arithmetic coding for bit-plane coding (CBACBP), for the enhancement layer of fine granular scalable (FGS) videocoding. The...
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In this paper, we propose a new efficient entropy coding scheme, namely context-based binary arithmetic coding for bit-plane coding (CBACBP), for the enhancement layer of fine granular scalable (FGS) videocoding. The basic structure of proposed CBACBP is based on the traditional bit-plane coding of MPEG-4 FGS. However, in order to enhance the coding efficiency of bit-plane coding, a newly designed context-based binary arithmetic coding scheme is used. In CBACBP, we apply three types of probability estimation techniques.. The first type relies on local information of a given symbol to code, such as bit-plane level, data level and frequency component. In the second type, the preceding symbols in the same and/or higher bit-planes are used. In the third type, we consider complexity of a block including the symbol based on the number of coded nonzero coefficients in the block. Experimental results show that the proposed CBACBP improves the PSNR up to 1.2 and 0.5 dB compared with MPEG4 FGS and JSVM, respectively.
This paper presents a strategy that efficiently allocates the limited resource and still maintains the coding performance for the spatial scalability of H.264/SVC. An integrated computation-scalable algorithm is propo...
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This paper presents a strategy that efficiently allocates the limited resource and still maintains the coding performance for the spatial scalability of H.264/SVC. An integrated computation-scalable algorithm is proposed on the basis of priority-based mode decision (PBMD) and activity-based motion estimation (ABME). The rate-distortion cost (RD-cost) of base layer is utilized as the priority to decide the mode in the enhancement layer, and the motion vector difference (MVD) in the base layer is employed to determine the search range as well. Through the proposed approach, computation complexity of the enhancement layer could be reduced efficiently and well allocated. A fast algorithm with early termination mechanism is also proposed in this paper. Experimental results demonstrate that the various rate-distortion and time-saving performances with computation scalability are realized.
Recently, the H.264/AVC standard has been extended to incorporate scalable video coding (SVC). SVC offers the advantage of scalable (layered) coding, but has the disadvantage of a highly increased computational comple...
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Recently, the H.264/AVC standard has been extended to incorporate scalable video coding (SVC). SVC offers the advantage of scalable (layered) coding, but has the disadvantage of a highly increased computational complexity at the encoder side when dealing with spatial scalability. To restrict the increase in required processing power, fast mode decision models for spatial enhancement layers have been proposed in literature. We propose a novel generic fast mode decision model for spatial enhancement layers for both P and B frames based on both the quantization of the enhancement layer and the correlation between the macroblock type in the enhancement layer and the co-located macroblock in the reference layer. In this paper, an evaluation of the proposed model and comparison with a state-of-the-art model is given. Results show that the proposed technique performs exceptionally well for spatial scalability. For both dyadic and non-dyadic spatial scalability, we achieve an average time saving of 75%, while only a slight bit rate increase of 2.23% and a minor PSNR decrease of 0.46 dB are measured. Compared with state of the art techniques, we further halve the complexity while having comparable rate-distortion results.
Motion scalability is designed to improve the coding efficiency of a scalable video coding framework, especially in the medium to low range of decoding bit rates and spatial resolutions. In order to fully benefit from...
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Motion scalability is designed to improve the coding efficiency of a scalable video coding framework, especially in the medium to low range of decoding bit rates and spatial resolutions. In order to fully benefit from the superiority of motion scalability, a rate-distortion optimized bitstream extractor, which determines the optimal motion quality layer for any specific decoding scenario, is required. In this paper, the determination process first starts off with a brute force searching algorithm. Although guaranteed by the optimal performance within the search domain, it suffers from high computational complexities. Two properties, i.e., the monotonically nondecreasing property and the unimodal property, are then derived to accurately describe the rate-distortion behavior of motion scalability. Based on these two properties, modified searching algorithms are proposed to reduce the complexity (up to five times faster) and to achieve the global optimality, even for those decoding scenarios outside the search domain.
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