This correspondence addresses the use of a jointsource-channelcoding strategy for enhancing the error resilience of images transmitted over a binary channel with additive Markov noise. In this scheme, inherent or re...
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This correspondence addresses the use of a jointsource-channelcoding strategy for enhancing the error resilience of images transmitted over a binary channel with additive Markov noise. In this scheme, inherent or residual (after sourcecoding) image redundancy is exploited at the receiver via a maximum a posteriori (MAP) channel detector. This detector, which is optimal in terms of minimizing the probability of error, also exploits the larger capacity of the channel with memory as opposed to the interleaved (memoryless) channel, We first consider MAP channel decoding of uncompressed two-tone and bit-plane encoded grey-level images. Next, we propose a scheme relying on unequal error protection and MAP detection for transmitting grey-level images compressed using discrete cosine transform (DCT), zonal coding, and quantization. Experimental results demonstrate that for various overall (source and channel) operational rates, significant performance improvements can be achieved over interleaved systems that do not incorporate image redundancy.
We propose a distortion optimal rate allocation algorithm for robust transmission of embedded bitstreams over noisy channels. The algorithm is based on the backward application of a Viterbi-like algorithm to a search ...
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We propose a distortion optimal rate allocation algorithm for robust transmission of embedded bitstreams over noisy channels. The algorithm is based on the backward application of a Viterbi-like algorithm to a search trellis, and can be applied to both scenarios of fixed and variable channel packet length problems, referred to as FPP and VPP, respectively. For the VPP, the complexity of the algorithm is comparable to the welt-known dynamic programming approach of Chande and Farvardin. For the FPP, where no low-complexity algorithm is known, the complexity of the proposed algorithm is O(N-2), where N is the number of transmitted packets.
In this paper, based on previously work in [7] and [9], a joint method of optimize source and channel rate allocation is proposed based the dependence and the attenuation of error propagation between video frames. It ...
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ISBN:
(纸本)078039335X
In this paper, based on previously work in [7] and [9], a joint method of optimize source and channel rate allocation is proposed based the dependence and the attenuation of error propagation between video frames. It is assumed that the source coders rely on motion-compensated prediction, and thus error propagation will contribute significantly to the degradation of the reconstructed video. The rate allocation method is based upon generation of operational distortion-rate characteristics. In order to reduce computational complexity, the channel code performance is modeled and the model of the attenuation of intensity of error propagation is employed to generate these rate-distortion surfaces. An analytic method for computing optimal rate allocation both frames in a video sequence is then introduced. Finally, the results of rate allocation and unequal error protection are shown for H.264 compressed video used in convolutional codes.
A novel rate-optimal rate allocation algorithm is proposed for parallel transmission of scalable images in multi-channel systems. Scalable images are transmitted via fixed-length packets. The proposed algorithm select...
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ISBN:
(纸本)9780819466211
A novel rate-optimal rate allocation algorithm is proposed for parallel transmission of scalable images in multi-channel systems. Scalable images are transmitted via fixed-length packets. The proposed algorithm selects a subchannel as well as a channel code rate for each packet, based on the signal-to-noise ratios (SNR) of the subchannels. The resulting scheme provides unequal error protection of source bits. Applications to JPEC2000 transmission show that significant UEP gains are achieved over equal error protection (EEP) schemes.
Following the jointsource and channelcoding paradigm, we propose in this article an application controlling strategy to allow fast adaptation of multimedia transmission to the impairments of an IP wireless network. ...
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ISBN:
(纸本)9781457705397
Following the jointsource and channelcoding paradigm, we propose in this article an application controlling strategy to allow fast adaptation of multimedia transmission to the impairments of an IP wireless network. To this purpose, a semi-analytical prediction algorithm of the video stream perceived quality of service (PQoS) expressed as the end-to-end distortion (EED) is introduced, that takes into account the distortions due to the diverse treatments of compression, transmission and decoding for a group of pictures (GOP) subject to an imperfect communication channel. This algorithm allows to define the parameters providing the best perceived quality at the receiver side in terms both of compression and optionally of error correcting redundancy insertion to minimise the error impact with a GOP adaptation rate, as demonstrated by the results presented for H.264/AVC streams transmitted in various channel configurations.
In this contribution me discuss linear signal representations satisfying a perfect reconstruction (PR) property, Such signal representations arise frequently in the context of signal compression (lossy sourcecoding),...
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In this contribution me discuss linear signal representations satisfying a perfect reconstruction (PR) property, Such signal representations arise frequently in the context of signal compression (lossy sourcecoding), In classical transform coders and in subband (wavelet) coders, critically sampled signal representations are used, which exhibit no inherent redundancy. Overcomplete representations can be used for signal compression as well (as e.g. in pyramid coding schemes). Such representations are defined by the forward transform which is part of the encoder. Since the forward transform is not invertible as in the case of classical transform coders, it is not obvious, which backward transform shall be employed at the decoder. Because overcomplete representations are inherently redundant, there are infinitely many possible backward transforms, A proper choice of the backward transform can be exploited for error resilient decoding;this means that overcomplete signal representations can be used as jointsource/channel codes, A decoding algorithm based on set theoretic estimation (a variant of projections onto convex sets (POCS)) is derived. As application error correction results are given for a Laplacian pyramid image coder.
In this paper, based on previously work in [7] and [9],a joint method of optimize source and channel rate allocation is proposed based the dependence and the attenuation of error propagation between video frames. It i...
详细信息
ISBN:
(纸本)078039335X
In this paper, based on previously work in [7] and [9],a joint method of optimize source and channel rate allocation is proposed based the dependence and the attenuation of error propagation between video frames. It is assumed that the source coders rely on motion-compensated prediction, and thus error propagation will contribute significantiy to the degradation of the reconstructed video. The rate allocation method is based upon generation of operational distortion-rate characteristics. In order to reduce computational complexity, the channel code performance is modeled and the model of the attenuation of intensity of error propagation is employed to generate these rate-distortion surfaces. An analytic method for computing optimal rate allocation both frames in a video sequence is then introduced. Finally, the results of rate allocation and unequal error protection are shown for H.264 compressed video used in convolutional codes.
Following the jointsource and channelcoding paradigm, we propose in this article an application controlling strategy to allow fast adaptation of multimedia transmission to the impairments of an IP wireless network. ...
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ISBN:
(纸本)9781457705380
Following the jointsource and channelcoding paradigm, we propose in this article an application controlling strategy to allow fast adaptation of multimedia transmission to the impairments of an IP wireless network. To this purpose, a semi-analytical prediction algorithm of the video stream perceived quality of service (PQoS) expressed as the end-to-end distortion (EED) is introduced, that takes into account the distortions due to the diverse treatments of compression, transmission and decoding for a group of pictures (GOP) subject to an imperfect communication channel. This algorithm allows to define the parameters providing the best perceived quality at the receiver side in terms both of compression and optionally of error correcting redundancy insertion to minimise the error impact with a GOP adaptation rate, as demonstrated by the results presented for H.264/AVC streams transmitted in various channel configurations.
A globally optimal solution to vector quantization (VQ) index assignment on noisy channel, the evolutionary algorithm based index assignment algorithm (EAIAA), is presented. The algorithm yields a significant reductio...
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A globally optimal solution to vector quantization (VQ) index assignment on noisy channel, the evolutionary algorithm based index assignment algorithm (EAIAA), is presented. The algorithm yields a significant reduction in average distortion due to channel errors, over conventional arbitrary index assignment, as confirmed by experimental results over the memoryless binary symmetric channel (BSC) for any bit error.
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