In the studies related to multiple description coding (MDC), applying zero padding not only improves the spatial correlation between descriptions but also increases their sizes. However, as we pad more zeros, the spat...
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In the studies related to multiple description coding (MDC), applying zero padding not only improves the spatial correlation between descriptions but also increases their sizes. However, as we pad more zeros, the spatial correlation does not improve linearly. Therefore, the distortion is not reduced as the same amount when the size increases. In this paper, we focus on how to efficiently find an acceptable trade-off between the number of padded zeros and the increase of distortion in MDC. In this paper, we propose two distortion estimations for MDC with zero padding based on spatial quincunx distribution, which are standard deviation for distortion estimation and triangular linear approximation distortion estimation (TLA-DE) to efficiently calculate the distortion for the number of padded zeros atthe horizontal direction. In order to search for the acceptable number of padded zeros, we propose two search methods, Naive Search and Best Division Search, which are both based on the proposed rate-distortion trade-off indicator. Our experiments result show that the worst error of distortion estimation by TLA-DE is up to 18%, but the average is 5.5% with 95% confidence level. The executing time of best division search is about two times faster than that of naive search for 11 test sequences. To sum up, we confirm that the acceptable trade-off between rate and distortion in low computational complexity can be found by using the best division search on TLA-DE.
One of the important issues in multiple description coding (MDC) for image and video signals is to compose pictures of the "best" quality when more than one description is received at the decoder side. To th...
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ISBN:
(纸本)9780819482341
One of the important issues in multiple description coding (MDC) for image and video signals is to compose pictures of the "best" quality when more than one description is received at the decoder side. To this goal, a transform-domain overlapping technique combined with some necessary translations in the transform domain is proposed in the popular MDC schemes with staggered quantizers. However, the achievable gain is rather limited. In this paper, we formulate this enhancement problem as a total variation (TV) regularized optimization constrained by the knowledge of the quantization intervals of the DCT coefficients of each composed picture. In this TV-based approach, the transform-domain overlapping technique is used to find the more accurate quantization intervals in which the true DCT coefficients will fall while receiving more than one description. Simulation results demonstrate that such a TV-based enhancement yields a higher quality gain in both objective (e.g. PSNR-based) and subjective (i.e. visual perception) evaluations than using the transform-domain overlapping technique.
We derive a single-letter lower bound on the minimum sum rate of multiple description coding with symmetric distortion constraints. For the binary uniform source with the erasure distortion measure or Hamming distorti...
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We derive a single-letter lower bound on the minimum sum rate of multiple description coding with symmetric distortion constraints. For the binary uniform source with the erasure distortion measure or Hamming distortion measure, this lower bound can be evaluated with the aid of certain minimax theorems. A similar minimax theorem is established in the quadratic Gaussian setting, which is further leveraged to analyze the special case where the minimum sum rate subject to two levels of distortion constraints (with the second level imposed on the complete set of descriptions) is attained;in particular, we determine the minimum achievable distortions at the intermediate levels.
A single-letter lower bound on the sum rate of multiple description coding with tree-structured distortion constraints is established by generalizing Ozarow's celebrated converse argument through the introduction ...
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A single-letter lower bound on the sum rate of multiple description coding with tree-structured distortion constraints is established by generalizing Ozarow's celebrated converse argument through the introduction of auxiliary random variables that form a Markov tree. For the quadratic vector Gaussian case, this lower bound is shown to be achievable by an extended El Gamal-Cover scheme, yielding a complete characterization of the minimum sum rate.
Different system may have different request on coding efficiency and security, even the characteristics of the unreliable networks are fixed, such as bit error rate, packet loss rate and bandwidth. In this paper, a no...
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ISBN:
(纸本)9781612842547
Different system may have different request on coding efficiency and security, even the characteristics of the unreliable networks are fixed, such as bit error rate, packet loss rate and bandwidth. In this paper, a novel multiple description coding (MDC) scheme is presented for the unreliable networks, considering both the network characteristics and system request. An error-resilient problem based on MDSQ [1] method is proposed and analyzed, and then an iterative redundancy-control method is designed based on ERMDC [2] by index pair ordering. Accordingly, a fast IA method is proposed only considering the high redundancy case. Simulation results show that the redundancy can be easily and precisely adjusted to meet all the requests. Meanwhile, the error resilience and R-D bound of MDC is self-adaptively guaranteed well enough for all cases.
The data delivery performance of multiple description coding (MDC) over unreliable network with capacity constraints is always related with three factors: redundancy rate, packet loss rate (PLR), bit error rate (BER)....
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ISBN:
(纸本)9780769543529
The data delivery performance of multiple description coding (MDC) over unreliable network with capacity constraints is always related with three factors: redundancy rate, packet loss rate (PLR), bit error rate (BER). It is supposed that the packet losses have been settled by MDC with certain redundancy. We simplified the network-adaptive data delivery problem to only relating with the redundancy rate factor, because the bit-error resilience of the system can be self-adaptively guaranteed well enough for any redundancy case by the proposed codeword ordering method. Then the problem becomes explicit, and is easily and precisely solved by the proposed iterative redundancy control method. The proposed scheme is an extension of scalar quantization (SQ) based MDC, either balanced or unbalanced case. The related index assignment (IA) problem is well solved, and the R-D bound is proved trending to be optimal. This method can be incorporated into any SQ-based MDC system to simplify the network-adaptive delivery problem, fully considering the related factors.
In this paper, we propose a multiple description coding (MDC) method for reliable transmission of compressed time consistent 3D dynamic meshes. It trades off reconstruction quality for error resilience to provide the ...
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ISBN:
(纸本)9781424443178
In this paper, we propose a multiple description coding (MDC) method for reliable transmission of compressed time consistent 3D dynamic meshes. It trades off reconstruction quality for error resilience to provide the best expected reconstruction of 3D mesh sequence at the decoder side. The method is based on partitioning the mesh vertices into two sets and encoding each set independently by a 3D dynamic mesh coder. The encoded independent bitstreams or so-called descriptions are transmitted independently. The 3D dynamic mesh coder is based on predictive coding with spatial and temporal layered decomposition. In addition, the proposed method allows for different redundancy allocations by duplicating a number of encoded spatial layers in both sets. The algorithm is evaluated with redundancy-rate-distortion curves and flexible trade-off between redundancy and side distortions can be achieved.
multiple description coding (MDC) has been proposed as a source coding technique that is robust to channel errors for video transmission. MDC generates multiple independent bit-streams, where the multiple bit-streams ...
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ISBN:
(纸本)9781424435098
multiple description coding (MDC) has been proposed as a source coding technique that is robust to channel errors for video transmission. MDC generates multiple independent bit-streams, where the multiple bit-streams are referred to as multipledescriptions (MD). Furthermore, it enables a useful reproduction of the signal when any description is received correctly. This paper proposes a new multicast heuristic algorithm, that attempts to take the benefit of MDC properties and multiple paths, to improve the user's satisfaction for a group of heterogeneous destinations in wireless ad hoe network. Extensive simulations clearly demonstrate the effectiveness of the proposed algorithm in improving the user's satisfaction irrespective of the number of destinations in the multicast group.
This paper proposes a rate controlled redundancy-adaptive multipledescription video coding method. The method adjusts the level of redundancy allocated to each macroblock based on an end to end distortion model that ...
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ISBN:
(纸本)9781424479948
This paper proposes a rate controlled redundancy-adaptive multipledescription video coding method. The method adjusts the level of redundancy allocated to each macroblock based on an end to end distortion model that takes into account the effects of error propagation and coneealment. Rate control at the macroblock level, ensures that the total bit-rate of all descriptions does not exceed the target rate. Results show that the proposed MDC codec can adapt very well to changing transmission conditions. When coupled with a MIMO architecture, performance gains of up to 14 dB were recorded over single description transmission at high packet error rates and no perceptible performance deficit at low packet error rates.
multiple description coding (MDC) and forward error control (FEC) are two frequently used techniques for improving transport performance on lossy packet networks. Typically, these two techniques are used separately an...
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ISBN:
(纸本)9781424415632
multiple description coding (MDC) and forward error control (FEC) are two frequently used techniques for improving transport performance on lossy packet networks. Typically, these two techniques are used separately and independently with resulting performance dependent on network conditions' the choice of coding parameters and the applications being transported. In this paper we propose and analyze a joint MDC and FEC coding approach for delay-constrained applications on congested networks under some idealized modeling assumptions which are, nevertheless, sufficient to draw some qualitative conclusions. Specifically, for fixed delay constraints we show that under a range of operating parameters, there is an optimal FEC coding block size, channel coding rate and assignment of MDC rates which can achieve significantly improved end-to-end performance, compared to the performance achieved by using only MDC or FEC alone.
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