The demand for efficient scalable video codecs has constantly been on the rise in response to the increase in the variety of services and QoS requirements in multimedia networks. Existing standardization efforts, such...
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ISBN:
(纸本)9780780397538
The demand for efficient scalable video codecs has constantly been on the rise in response to the increase in the variety of services and QoS requirements in multimedia networks. Existing standardization efforts, such as the Scalable Video coding extension of the H.264/AVC standard, do not offer efficient error resilient protection for all the different levels of video enhancement. We developed a multipledescription scalable video coding technique that offers complementary and independently decodable descriptions, offering acceptable video quality even if only one of them is successfully received. Performance evaluations show that our scheme delivers an average improvement of 5 dB for single channel decoding and an improvement of 2 dB on average for packet loss simulations when compared with the UXP protected SD-SVC and the multiple-description motion compensated temporal filtering (MD-MCTF) scheme at comparable redundancy levels.
This paper presents a video coding method that improves error resilient functionality of H.264 with good coding efficiency. The method is based on PD (polyphase downsampling) multiple description coding. The only chan...
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This paper presents a video coding method that improves error resilient functionality of H.264 with good coding efficiency. The method is based on PD (polyphase downsampling) multiple description coding. The only changes to H.264 are inserting PD before the DCT process and having new data partitioning NAL units. A coded slice is sent on 3 data partitioning NAL units. A header NAL unit contains motion vectors and block modes. Each of the other two NAL units contains a description generated by PD multiple description coding. The experimental results on all 9 of the test sequences of JVT SVC show that the proposed method gives 0.5 to 5 dB enhancement over the existing H.264 FMO checker board mode with motion vector based error-concealment.
This paper is about the design and analysis of an index-assignment (IA)-based multiple-descriptioncoding scheme for the n-channel asymmetric case. We use entropy constrained lattice vector quantization and restrict a...
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This paper is about the design and analysis of an index-assignment (IA)-based multiple-descriptioncoding scheme for the n-channel asymmetric case. We use entropy constrained lattice vector quantization and restrict attention to simple reconstruction functions, which are given by the inverse IA function when all descriptions are received or otherwise by a weighted average of the received descriptions. We consider smooth sources with finite differential entropy rate and MSE fidelity criterion. As in previous designs, our construction is based on nested lattices which are combined through a single IA function. The results are exact under high-resolution conditions and asymptotically as the nesting ratios of the lattices approach infinity. For any n, the design is asymptotically optimal within the class of IA-based schemes. Moreover, in the case of two descriptions and finite lattice vector dimensions greater than one, the performance is strictly better than that of existing designs. In the case of three descriptions, we show that in the limit of large lattice vector dimensions, points on the inner bound of Pradhan et al. can be achieved. Furthermore, for three descriptions and finite lattice vector dimensions, we show that the IA-based approach yields, in the symmetric case, a smaller rate loss than the recently proposed source-splitting approach.
A wavelet subdivision surfaces based multipledescription 3D model coding with optimal reconstruction filtering approach is proposed in this paper to transmit 3D models over mediums with possible packet loss with high...
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ISBN:
(纸本)9781424456536
A wavelet subdivision surfaces based multipledescription 3D model coding with optimal reconstruction filtering approach is proposed in this paper to transmit 3D models over mediums with possible packet loss with higher quality. The proposed method is based on the wavelet subdivision surfaces strategy for 3D model coding and introduces optimal reconstruction filtering. Initially, remeshing is performed for any 3D model to obtain a semi-regular mesh structure which includes an irregular base mesh and regular wavelet (detail) coefficients of finer levels. Next, multipledescriptions of detail coefficients are obtained using multipledescription Scalar Quantization (MDSQ) to be encoded using SPIHT. In the proposed approach, reconstructed multipledescriptions are applied to optimal filters, that are obtained at the encoder so as to reduce the reconstruction error between the original model and encoded model. Each transmitted description therefore includes encoded 3D data as well as optimal reconstruction filter coefficients. Experimental results show that the optimal reconstruction filtering approach reduces the distortion of standard MDSQ based 3D model coding.
A multiple description coding (MDC) technique for 3-D surface geometry is proposed in this work. The encoder uses a plane-based representation to describe point samples. Then, those plane primitives are classified int...
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ISBN:
(纸本)0819464899
A multiple description coding (MDC) technique for 3-D surface geometry is proposed in this work. The encoder uses a plane-based representation to describe point samples. Then, those plane primitives are classified into two disjoint subsets or two descriptions, each of which provides equal contribution in 3-D surface description. The two descriptions are compressed and transmitted over distinct channels. At the decoder, if both channels are available, the descriptions are decoded and merged together to reconstruct a high quality surface. If only one channel is available, we employ a surface interpolation method to fill visual holes and reconstruct a smooth surface. Therefore, the proposed algorithm can provide an acceptable reconstruction even though one channel is totally lost. Simulation results demonstrate that the proposed algorithm is a promising scheme for 3-D data transmission over noisy channels.
In this paper, a self-recovery image authentication technique is proposed using randomly-sized blocks. To dived an image into randomly-sized blocks, it undergoes recursive arbitrarily-asymmetric quad tree partitioning...
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ISBN:
(纸本)9781424479948
In this paper, a self-recovery image authentication technique is proposed using randomly-sized blocks. To dived an image into randomly-sized blocks, it undergoes recursive arbitrarily-asymmetric quad tree partitioning. multiple description coding (MDC) that enhances reliability of altered block recovery, is utilized to generate two block descriptions. We propose the use of a chain with multiple links for embedding several signature copies and two descriptions per block in arbitrarily distant blocks. The experimental results deposit that the proposed technique successfully both localizes and compensates the alterations. Furthermore, it is robust against the vector quantization (VQ) attack.
multiple description coding (MDC) provides stable wireless multimedia communications with the help of multiple transmission paths, while distributed video coding (DVC) effectively shifts the encoder complexity to deco...
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ISBN:
(纸本)9781424474936
multiple description coding (MDC) provides stable wireless multimedia communications with the help of multiple transmission paths, while distributed video coding (DVC) effectively shifts the encoder complexity to decoder for mobile media devices. We proposed to combine MDC with DVC, abbreviated as MDVC, to construct a reliable and efficient video codec system. To improve the codec performance, the DPCM prediction gain is exploited from the correlations among sub-video sequences inside the MDVC to increase the reconstructed video quality. In addition, a MDVC central decoder control method, operated dynamically at frame-level, is proposed to improve the adaptation capability, as compared to the current MDC central decoder that selects one best description for the output video. The intra-and inter-correlations among MDC descriptions were investigated to make this frame selection decision for the central decoder. Simulations showed that the proposed MDVC control method demonstrates higher average PSNR and lower PSNR variations of the output videos, with the help of DPCM prediction gain and the efficient central decoder control method that correctly selected high quality WZ frames for low quality key-frames.
Average throughput maximization has commonly been used as an alternative to image or video average distortion minimization. However, as the throughput-distortion curve is non-linear, throughput maximization can be ver...
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ISBN:
(纸本)9781424464043
Average throughput maximization has commonly been used as an alternative to image or video average distortion minimization. However, as the throughput-distortion curve is non-linear, throughput maximization can be very different from distortion minimization if the variance of the throughput is large. Under high channel quality variability, the variance of the throughput will be high. multiple description coding with unequal error protection is a promising technique for the transmission of progressive images when there exists a high variability of the channel conditions. In this paper, we consider both the variance and the average of the throughput when deciding the constellation size for adaptive modulation in an OFDM system used for transmitting progressively-coded images with multiple description coding. Simulation results show that in an adaptive modulated image transmission system, taking into account both moments of the throughput achieves better performance than a system considering average throughput alone.
This paper proposes a multiple description coding scheme based on a multi-loop structure, which prevents drift distortion accumulation in intra predicted slices. The drift is compensated by generating a controlled amo...
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ISBN:
(纸本)9781424456536;9781424456543
This paper proposes a multiple description coding scheme based on a multi-loop structure, which prevents drift distortion accumulation in intra predicted slices. The drift is compensated by generating a controlled amount of side information used by the decoder when-ever any description is lost in the corresponding network path. The experimental results show that intra predicted slices do not suffer from drift and their quality is significantly improved (e.g., 6-8 dB) at reduced redundancy cost, (e.g., 0.2-0.25), in comparison with the open loop implementation. Error propagation in subsequent frames is also evaluated when one description is lost for a whole frame and for two rows of macroblocks. In both cases the overall video quality is significantly improved and considering normal GOP sizes the redundancy introduced by the proposed scheme is negligible.
Video transmission over unreliable networks presents new challenges for research in video coding. In fact, in video coders that use predictive coding schemes, even a single packet loss may cause errors during the deco...
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Video transmission over unreliable networks presents new challenges for research in video coding. In fact, in video coders that use predictive coding schemes, even a single packet loss may cause errors during the decoding process propagating in time. A way to increase the robustness of the coded stream and reduce the length of error propagation is the use of a multiple description coding (MDC) technique. The aim of this paper is to apply a novel sequence-based error-concealment (EC) algorithm to an unbalanced MD video coding system that generates both a high-quality (HQ) and a low-quality (LQ) description. In order to recover a loss in the current frames, the EC algorithm takes into account not only the spatial/temporal neighboring of the region the lost data correspond to, but also what is going to happen in a significant number of future frames looking both the HQ and the LQ descriptions. The sequence-based EC algorithm presents good performances when applied to video streams. The comparison with concurrent error-resilience techniques shows interesting results. (C) 2006 Elsevier B.V. All rights reserved.
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